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linux/drivers/serial/mpsc.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers 
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

2092 lines
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/*
* Generic driver for the MPSC (UART mode) on Marvell parts (e.g., GT64240,
* GT64260, MV64340, MV64360, GT96100, ... ).
*
* Author: Mark A. Greer <mgreer@mvista.com>
*
* Based on an old MPSC driver that was in the linuxppc tree. It appears to
* have been created by Chris Zankel (formerly of MontaVista) but there
* is no proper Copyright so I'm not sure. Apparently, parts were also
* taken from PPCBoot (now U-Boot). Also based on drivers/serial/8250.c
* by Russell King.
*
* 2004 (c) MontaVista, Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
/*
* The MPSC interface is much like a typical network controller's interface.
* That is, you set up separate rings of descriptors for transmitting and
* receiving data. There is also a pool of buffers with (one buffer per
* descriptor) that incoming data are dma'd into or outgoing data are dma'd
* out of.
*
* The MPSC requires two other controllers to be able to work. The Baud Rate
* Generator (BRG) provides a clock at programmable frequencies which determines
* the baud rate. The Serial DMA Controller (SDMA) takes incoming data from the
* MPSC and DMA's it into memory or DMA's outgoing data and passes it to the
* MPSC. It is actually the SDMA interrupt that the driver uses to keep the
* transmit and receive "engines" going (i.e., indicate data has been
* transmitted or received).
*
* NOTES:
*
* 1) Some chips have an erratum where several regs cannot be
* read. To work around that, we keep a local copy of those regs in
* 'mpsc_port_info'.
*
* 2) Some chips have an erratum where the ctlr will hang when the SDMA ctlr
* accesses system mem with coherency enabled. For that reason, the driver
* assumes that coherency for that ctlr has been disabled. This means
* that when in a cache coherent system, the driver has to manually manage
* the data cache on the areas that it touches because the dma_* macro are
* basically no-ops.
*
* 3) There is an erratum (on PPC) where you can't use the instruction to do
* a DMA_TO_DEVICE/cache clean so DMA_BIDIRECTIONAL/flushes are used in places
* where a DMA_TO_DEVICE/clean would have [otherwise] sufficed.
*
* 4) AFAICT, hardware flow control isn't supported by the controller --MAG.
*/
#if defined(CONFIG_SERIAL_MPSC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/mv643xx.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <asm/irq.h>
#if defined(CONFIG_SERIAL_MPSC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#define MPSC_NUM_CTLRS 2
/*
* Descriptors and buffers must be cache line aligned.
* Buffers lengths must be multiple of cache line size.
* Number of Tx & Rx descriptors must be powers of 2.
*/
#define MPSC_RXR_ENTRIES 32
#define MPSC_RXRE_SIZE dma_get_cache_alignment()
#define MPSC_RXR_SIZE (MPSC_RXR_ENTRIES * MPSC_RXRE_SIZE)
#define MPSC_RXBE_SIZE dma_get_cache_alignment()
#define MPSC_RXB_SIZE (MPSC_RXR_ENTRIES * MPSC_RXBE_SIZE)
#define MPSC_TXR_ENTRIES 32
#define MPSC_TXRE_SIZE dma_get_cache_alignment()
#define MPSC_TXR_SIZE (MPSC_TXR_ENTRIES * MPSC_TXRE_SIZE)
#define MPSC_TXBE_SIZE dma_get_cache_alignment()
#define MPSC_TXB_SIZE (MPSC_TXR_ENTRIES * MPSC_TXBE_SIZE)
#define MPSC_DMA_ALLOC_SIZE (MPSC_RXR_SIZE + MPSC_RXB_SIZE + \
MPSC_TXR_SIZE + MPSC_TXB_SIZE + \
dma_get_cache_alignment() /* for alignment */)
/* Rx and Tx Ring entry descriptors -- assume entry size is <= cacheline size */
struct mpsc_rx_desc {
u16 bufsize;
u16 bytecnt;
u32 cmdstat;
u32 link;
u32 buf_ptr;
} __attribute((packed));
struct mpsc_tx_desc {
u16 bytecnt;
u16 shadow;
u32 cmdstat;
u32 link;
u32 buf_ptr;
} __attribute((packed));
/*
* Some regs that have the erratum that you can't read them are are shared
* between the two MPSC controllers. This struct contains those shared regs.
*/
struct mpsc_shared_regs {
phys_addr_t mpsc_routing_base_p;
phys_addr_t sdma_intr_base_p;
void __iomem *mpsc_routing_base;
void __iomem *sdma_intr_base;
u32 MPSC_MRR_m;
u32 MPSC_RCRR_m;
u32 MPSC_TCRR_m;
u32 SDMA_INTR_CAUSE_m;
u32 SDMA_INTR_MASK_m;
};
/* The main driver data structure */
struct mpsc_port_info {
struct uart_port port; /* Overlay uart_port structure */
/* Internal driver state for this ctlr */
u8 ready;
u8 rcv_data;
tcflag_t c_iflag; /* save termios->c_iflag */
tcflag_t c_cflag; /* save termios->c_cflag */
/* Info passed in from platform */
u8 mirror_regs; /* Need to mirror regs? */
u8 cache_mgmt; /* Need manual cache mgmt? */
u8 brg_can_tune; /* BRG has baud tuning? */
u32 brg_clk_src;
u16 mpsc_max_idle;
int default_baud;
int default_bits;
int default_parity;
int default_flow;
/* Physical addresses of various blocks of registers (from platform) */
phys_addr_t mpsc_base_p;
phys_addr_t sdma_base_p;
phys_addr_t brg_base_p;
/* Virtual addresses of various blocks of registers (from platform) */
void __iomem *mpsc_base;
void __iomem *sdma_base;
void __iomem *brg_base;
/* Descriptor ring and buffer allocations */
void *dma_region;
dma_addr_t dma_region_p;
dma_addr_t rxr; /* Rx descriptor ring */
dma_addr_t rxr_p; /* Phys addr of rxr */
u8 *rxb; /* Rx Ring I/O buf */
u8 *rxb_p; /* Phys addr of rxb */
u32 rxr_posn; /* First desc w/ Rx data */
dma_addr_t txr; /* Tx descriptor ring */
dma_addr_t txr_p; /* Phys addr of txr */
u8 *txb; /* Tx Ring I/O buf */
u8 *txb_p; /* Phys addr of txb */
int txr_head; /* Where new data goes */
int txr_tail; /* Where sent data comes off */
/* Mirrored values of regs we can't read (if 'mirror_regs' set) */
u32 MPSC_MPCR_m;
u32 MPSC_CHR_1_m;
u32 MPSC_CHR_2_m;
u32 MPSC_CHR_10_m;
u32 BRG_BCR_m;
struct mpsc_shared_regs *shared_regs;
};
/* Hooks to platform-specific code */
int mpsc_platform_register_driver(void);
void mpsc_platform_unregister_driver(void);
/* Hooks back in to mpsc common to be called by platform-specific code */
struct mpsc_port_info *mpsc_device_probe(int index);
struct mpsc_port_info *mpsc_device_remove(int index);
/* Main MPSC Configuration Register Offsets */
#define MPSC_MMCRL 0x0000
#define MPSC_MMCRH 0x0004
#define MPSC_MPCR 0x0008
#define MPSC_CHR_1 0x000c
#define MPSC_CHR_2 0x0010
#define MPSC_CHR_3 0x0014
#define MPSC_CHR_4 0x0018
#define MPSC_CHR_5 0x001c
#define MPSC_CHR_6 0x0020
#define MPSC_CHR_7 0x0024
#define MPSC_CHR_8 0x0028
#define MPSC_CHR_9 0x002c
#define MPSC_CHR_10 0x0030
#define MPSC_CHR_11 0x0034
#define MPSC_MPCR_FRZ (1 << 9)
#define MPSC_MPCR_CL_5 0
#define MPSC_MPCR_CL_6 1
#define MPSC_MPCR_CL_7 2
#define MPSC_MPCR_CL_8 3
#define MPSC_MPCR_SBL_1 0
#define MPSC_MPCR_SBL_2 1
#define MPSC_CHR_2_TEV (1<<1)
#define MPSC_CHR_2_TA (1<<7)
#define MPSC_CHR_2_TTCS (1<<9)
#define MPSC_CHR_2_REV (1<<17)
#define MPSC_CHR_2_RA (1<<23)
#define MPSC_CHR_2_CRD (1<<25)
#define MPSC_CHR_2_EH (1<<31)
#define MPSC_CHR_2_PAR_ODD 0
#define MPSC_CHR_2_PAR_SPACE 1
#define MPSC_CHR_2_PAR_EVEN 2
#define MPSC_CHR_2_PAR_MARK 3
/* MPSC Signal Routing */
#define MPSC_MRR 0x0000
#define MPSC_RCRR 0x0004
#define MPSC_TCRR 0x0008
/* Serial DMA Controller Interface Registers */
#define SDMA_SDC 0x0000
#define SDMA_SDCM 0x0008
#define SDMA_RX_DESC 0x0800
#define SDMA_RX_BUF_PTR 0x0808
#define SDMA_SCRDP 0x0810
#define SDMA_TX_DESC 0x0c00
#define SDMA_SCTDP 0x0c10
#define SDMA_SFTDP 0x0c14
#define SDMA_DESC_CMDSTAT_PE (1<<0)
#define SDMA_DESC_CMDSTAT_CDL (1<<1)
#define SDMA_DESC_CMDSTAT_FR (1<<3)
#define SDMA_DESC_CMDSTAT_OR (1<<6)
#define SDMA_DESC_CMDSTAT_BR (1<<9)
#define SDMA_DESC_CMDSTAT_MI (1<<10)
#define SDMA_DESC_CMDSTAT_A (1<<11)
#define SDMA_DESC_CMDSTAT_AM (1<<12)
#define SDMA_DESC_CMDSTAT_CT (1<<13)
#define SDMA_DESC_CMDSTAT_C (1<<14)
#define SDMA_DESC_CMDSTAT_ES (1<<15)
#define SDMA_DESC_CMDSTAT_L (1<<16)
#define SDMA_DESC_CMDSTAT_F (1<<17)
#define SDMA_DESC_CMDSTAT_P (1<<18)
#define SDMA_DESC_CMDSTAT_EI (1<<23)
#define SDMA_DESC_CMDSTAT_O (1<<31)
#define SDMA_DESC_DFLT (SDMA_DESC_CMDSTAT_O | \
SDMA_DESC_CMDSTAT_EI)
#define SDMA_SDC_RFT (1<<0)
#define SDMA_SDC_SFM (1<<1)
#define SDMA_SDC_BLMR (1<<6)
#define SDMA_SDC_BLMT (1<<7)
#define SDMA_SDC_POVR (1<<8)
#define SDMA_SDC_RIFB (1<<9)
#define SDMA_SDCM_ERD (1<<7)
#define SDMA_SDCM_AR (1<<15)
#define SDMA_SDCM_STD (1<<16)
#define SDMA_SDCM_TXD (1<<23)
#define SDMA_SDCM_AT (1<<31)
#define SDMA_0_CAUSE_RXBUF (1<<0)
#define SDMA_0_CAUSE_RXERR (1<<1)
#define SDMA_0_CAUSE_TXBUF (1<<2)
#define SDMA_0_CAUSE_TXEND (1<<3)
#define SDMA_1_CAUSE_RXBUF (1<<8)
#define SDMA_1_CAUSE_RXERR (1<<9)
#define SDMA_1_CAUSE_TXBUF (1<<10)
#define SDMA_1_CAUSE_TXEND (1<<11)
#define SDMA_CAUSE_RX_MASK (SDMA_0_CAUSE_RXBUF | SDMA_0_CAUSE_RXERR | \
SDMA_1_CAUSE_RXBUF | SDMA_1_CAUSE_RXERR)
#define SDMA_CAUSE_TX_MASK (SDMA_0_CAUSE_TXBUF | SDMA_0_CAUSE_TXEND | \
SDMA_1_CAUSE_TXBUF | SDMA_1_CAUSE_TXEND)
/* SDMA Interrupt registers */
#define SDMA_INTR_CAUSE 0x0000
#define SDMA_INTR_MASK 0x0080
/* Baud Rate Generator Interface Registers */
#define BRG_BCR 0x0000
#define BRG_BTR 0x0004
/*
* Define how this driver is known to the outside (we've been assigned a
* range on the "Low-density serial ports" major).
*/
#define MPSC_MAJOR 204
#define MPSC_MINOR_START 44
#define MPSC_DRIVER_NAME "MPSC"
#define MPSC_DEV_NAME "ttyMM"
#define MPSC_VERSION "1.00"
static struct mpsc_port_info mpsc_ports[MPSC_NUM_CTLRS];
static struct mpsc_shared_regs mpsc_shared_regs;
static struct uart_driver mpsc_reg;
static void mpsc_start_rx(struct mpsc_port_info *pi);
static void mpsc_free_ring_mem(struct mpsc_port_info *pi);
static void mpsc_release_port(struct uart_port *port);
/*
******************************************************************************
*
* Baud Rate Generator Routines (BRG)
*
******************************************************************************
*/
static void
mpsc_brg_init(struct mpsc_port_info *pi, u32 clk_src)
{
u32 v;
v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
v = (v & ~(0xf << 18)) | ((clk_src & 0xf) << 18);
if (pi->brg_can_tune)
v &= ~(1 << 25);
if (pi->mirror_regs)
pi->BRG_BCR_m = v;
writel(v, pi->brg_base + BRG_BCR);
writel(readl(pi->brg_base + BRG_BTR) & 0xffff0000,
pi->brg_base + BRG_BTR);
return;
}
static void
mpsc_brg_enable(struct mpsc_port_info *pi)
{
u32 v;
v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
v |= (1 << 16);
if (pi->mirror_regs)
pi->BRG_BCR_m = v;
writel(v, pi->brg_base + BRG_BCR);
return;
}
static void
mpsc_brg_disable(struct mpsc_port_info *pi)
{
u32 v;
v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
v &= ~(1 << 16);
if (pi->mirror_regs)
pi->BRG_BCR_m = v;
writel(v, pi->brg_base + BRG_BCR);
return;
}
static inline void
mpsc_set_baudrate(struct mpsc_port_info *pi, u32 baud)
{
/*
* To set the baud, we adjust the CDV field in the BRG_BCR reg.
* From manual: Baud = clk / ((CDV+1)*2) ==> CDV = (clk / (baud*2)) - 1.
* However, the input clock is divided by 16 in the MPSC b/c of how
* 'MPSC_MMCRH' was set up so we have to divide the 'clk' used in our
* calculation by 16 to account for that. So the real calculation
* that accounts for the way the mpsc is set up is:
* CDV = (clk / (baud*2*16)) - 1 ==> CDV = (clk / (baud << 5)) - 1.
*/
u32 cdv = (pi->port.uartclk / (baud << 5)) - 1;
u32 v;
mpsc_brg_disable(pi);
v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
v = (v & 0xffff0000) | (cdv & 0xffff);
if (pi->mirror_regs)
pi->BRG_BCR_m = v;
writel(v, pi->brg_base + BRG_BCR);
mpsc_brg_enable(pi);
return;
}
/*
******************************************************************************
*
* Serial DMA Routines (SDMA)
*
******************************************************************************
*/
static void
mpsc_sdma_burstsize(struct mpsc_port_info *pi, u32 burst_size)
{
u32 v;
pr_debug("mpsc_sdma_burstsize[%d]: burst_size: %d\n",
pi->port.line, burst_size);
burst_size >>= 3; /* Divide by 8 b/c reg values are 8-byte chunks */
if (burst_size < 2)
v = 0x0; /* 1 64-bit word */
else if (burst_size < 4)
v = 0x1; /* 2 64-bit words */
else if (burst_size < 8)
v = 0x2; /* 4 64-bit words */
else
v = 0x3; /* 8 64-bit words */
writel((readl(pi->sdma_base + SDMA_SDC) & (0x3 << 12)) | (v << 12),
pi->sdma_base + SDMA_SDC);
return;
}
static void
mpsc_sdma_init(struct mpsc_port_info *pi, u32 burst_size)
{
pr_debug("mpsc_sdma_init[%d]: burst_size: %d\n", pi->port.line,
burst_size);
writel((readl(pi->sdma_base + SDMA_SDC) & 0x3ff) | 0x03f,
pi->sdma_base + SDMA_SDC);
mpsc_sdma_burstsize(pi, burst_size);
return;
}
static inline u32
mpsc_sdma_intr_mask(struct mpsc_port_info *pi, u32 mask)
{
u32 old, v;
pr_debug("mpsc_sdma_intr_mask[%d]: mask: 0x%x\n", pi->port.line, mask);
old = v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m :
readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
mask &= 0xf;
if (pi->port.line)
mask <<= 8;
v &= ~mask;
if (pi->mirror_regs)
pi->shared_regs->SDMA_INTR_MASK_m = v;
writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
if (pi->port.line)
old >>= 8;
return old & 0xf;
}
static inline void
mpsc_sdma_intr_unmask(struct mpsc_port_info *pi, u32 mask)
{
u32 v;
pr_debug("mpsc_sdma_intr_unmask[%d]: mask: 0x%x\n", pi->port.line,mask);
v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m :
readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
mask &= 0xf;
if (pi->port.line)
mask <<= 8;
v |= mask;
if (pi->mirror_regs)
pi->shared_regs->SDMA_INTR_MASK_m = v;
writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
return;
}
static inline void
mpsc_sdma_intr_ack(struct mpsc_port_info *pi)
{
pr_debug("mpsc_sdma_intr_ack[%d]: Acknowledging IRQ\n", pi->port.line);
if (pi->mirror_regs)
pi->shared_regs->SDMA_INTR_CAUSE_m = 0;
writel(0, pi->shared_regs->sdma_intr_base + SDMA_INTR_CAUSE);
return;
}
static inline void
mpsc_sdma_set_rx_ring(struct mpsc_port_info *pi, struct mpsc_rx_desc *rxre_p)
{
pr_debug("mpsc_sdma_set_rx_ring[%d]: rxre_p: 0x%x\n",
pi->port.line, (u32) rxre_p);
writel((u32)rxre_p, pi->sdma_base + SDMA_SCRDP);
return;
}
static inline void
mpsc_sdma_set_tx_ring(struct mpsc_port_info *pi, struct mpsc_tx_desc *txre_p)
{
writel((u32)txre_p, pi->sdma_base + SDMA_SFTDP);
writel((u32)txre_p, pi->sdma_base + SDMA_SCTDP);
return;
}
static inline void
mpsc_sdma_cmd(struct mpsc_port_info *pi, u32 val)
{
u32 v;
v = readl(pi->sdma_base + SDMA_SDCM);
if (val)
v |= val;
else
v = 0;
wmb();
writel(v, pi->sdma_base + SDMA_SDCM);
wmb();
return;
}
static inline uint
mpsc_sdma_tx_active(struct mpsc_port_info *pi)
{
return readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_TXD;
}
static inline void
mpsc_sdma_start_tx(struct mpsc_port_info *pi)
{
struct mpsc_tx_desc *txre, *txre_p;
/* If tx isn't running & there's a desc ready to go, start it */
if (!mpsc_sdma_tx_active(pi)) {
txre = (struct mpsc_tx_desc *)(pi->txr +
(pi->txr_tail * MPSC_TXRE_SIZE));
dma_cache_sync((void *) txre, MPSC_TXRE_SIZE, DMA_FROM_DEVICE);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
invalidate_dcache_range((ulong)txre,
(ulong)txre + MPSC_TXRE_SIZE);
#endif
if (be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O) {
txre_p = (struct mpsc_tx_desc *)(pi->txr_p +
(pi->txr_tail *
MPSC_TXRE_SIZE));
mpsc_sdma_set_tx_ring(pi, txre_p);
mpsc_sdma_cmd(pi, SDMA_SDCM_STD | SDMA_SDCM_TXD);
}
}
return;
}
static inline void
mpsc_sdma_stop(struct mpsc_port_info *pi)
{
pr_debug("mpsc_sdma_stop[%d]: Stopping SDMA\n", pi->port.line);
/* Abort any SDMA transfers */
mpsc_sdma_cmd(pi, 0);
mpsc_sdma_cmd(pi, SDMA_SDCM_AR | SDMA_SDCM_AT);
/* Clear the SDMA current and first TX and RX pointers */
mpsc_sdma_set_tx_ring(pi, NULL);
mpsc_sdma_set_rx_ring(pi, NULL);
/* Disable interrupts */
mpsc_sdma_intr_mask(pi, 0xf);
mpsc_sdma_intr_ack(pi);
return;
}
/*
******************************************************************************
*
* Multi-Protocol Serial Controller Routines (MPSC)
*
******************************************************************************
*/
static void
mpsc_hw_init(struct mpsc_port_info *pi)
{
u32 v;
pr_debug("mpsc_hw_init[%d]: Initializing hardware\n", pi->port.line);
/* Set up clock routing */
if (pi->mirror_regs) {
v = pi->shared_regs->MPSC_MRR_m;
v &= ~0x1c7;
pi->shared_regs->MPSC_MRR_m = v;
writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
v = pi->shared_regs->MPSC_RCRR_m;
v = (v & ~0xf0f) | 0x100;
pi->shared_regs->MPSC_RCRR_m = v;
writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
v = pi->shared_regs->MPSC_TCRR_m;
v = (v & ~0xf0f) | 0x100;
pi->shared_regs->MPSC_TCRR_m = v;
writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
}
else {
v = readl(pi->shared_regs->mpsc_routing_base + MPSC_MRR);
v &= ~0x1c7;
writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
v = readl(pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
v = (v & ~0xf0f) | 0x100;
writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
v = readl(pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
v = (v & ~0xf0f) | 0x100;
writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
}
/* Put MPSC in UART mode & enabel Tx/Rx egines */
writel(0x000004c4, pi->mpsc_base + MPSC_MMCRL);
/* No preamble, 16x divider, low-latency, */
writel(0x04400400, pi->mpsc_base + MPSC_MMCRH);
if (pi->mirror_regs) {
pi->MPSC_CHR_1_m = 0;
pi->MPSC_CHR_2_m = 0;
}
writel(0, pi->mpsc_base + MPSC_CHR_1);
writel(0, pi->mpsc_base + MPSC_CHR_2);
writel(pi->mpsc_max_idle, pi->mpsc_base + MPSC_CHR_3);
writel(0, pi->mpsc_base + MPSC_CHR_4);
writel(0, pi->mpsc_base + MPSC_CHR_5);
writel(0, pi->mpsc_base + MPSC_CHR_6);
writel(0, pi->mpsc_base + MPSC_CHR_7);
writel(0, pi->mpsc_base + MPSC_CHR_8);
writel(0, pi->mpsc_base + MPSC_CHR_9);
writel(0, pi->mpsc_base + MPSC_CHR_10);
return;
}
static inline void
mpsc_enter_hunt(struct mpsc_port_info *pi)
{
pr_debug("mpsc_enter_hunt[%d]: Hunting...\n", pi->port.line);
if (pi->mirror_regs) {
writel(pi->MPSC_CHR_2_m | MPSC_CHR_2_EH,
pi->mpsc_base + MPSC_CHR_2);
/* Erratum prevents reading CHR_2 so just delay for a while */
udelay(100);
}
else {
writel(readl(pi->mpsc_base + MPSC_CHR_2) | MPSC_CHR_2_EH,
pi->mpsc_base + MPSC_CHR_2);
while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_EH)
udelay(10);
}
return;
}
static inline void
mpsc_freeze(struct mpsc_port_info *pi)
{
u32 v;
pr_debug("mpsc_freeze[%d]: Freezing\n", pi->port.line);
v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
readl(pi->mpsc_base + MPSC_MPCR);
v |= MPSC_MPCR_FRZ;
if (pi->mirror_regs)
pi->MPSC_MPCR_m = v;
writel(v, pi->mpsc_base + MPSC_MPCR);
return;
}
static inline void
mpsc_unfreeze(struct mpsc_port_info *pi)
{
u32 v;
v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
readl(pi->mpsc_base + MPSC_MPCR);
v &= ~MPSC_MPCR_FRZ;
if (pi->mirror_regs)
pi->MPSC_MPCR_m = v;
writel(v, pi->mpsc_base + MPSC_MPCR);
pr_debug("mpsc_unfreeze[%d]: Unfrozen\n", pi->port.line);
return;
}
static inline void
mpsc_set_char_length(struct mpsc_port_info *pi, u32 len)
{
u32 v;
pr_debug("mpsc_set_char_length[%d]: char len: %d\n", pi->port.line,len);
v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
readl(pi->mpsc_base + MPSC_MPCR);
v = (v & ~(0x3 << 12)) | ((len & 0x3) << 12);
if (pi->mirror_regs)
pi->MPSC_MPCR_m = v;
writel(v, pi->mpsc_base + MPSC_MPCR);
return;
}
static inline void
mpsc_set_stop_bit_length(struct mpsc_port_info *pi, u32 len)
{
u32 v;
pr_debug("mpsc_set_stop_bit_length[%d]: stop bits: %d\n",
pi->port.line, len);
v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
readl(pi->mpsc_base + MPSC_MPCR);
v = (v & ~(1 << 14)) | ((len & 0x1) << 14);
if (pi->mirror_regs)
pi->MPSC_MPCR_m = v;
writel(v, pi->mpsc_base + MPSC_MPCR);
return;
}
static inline void
mpsc_set_parity(struct mpsc_port_info *pi, u32 p)
{
u32 v;
pr_debug("mpsc_set_parity[%d]: parity bits: 0x%x\n", pi->port.line, p);
v = (pi->mirror_regs) ? pi->MPSC_CHR_2_m :
readl(pi->mpsc_base + MPSC_CHR_2);
p &= 0x3;
v = (v & ~0xc000c) | (p << 18) | (p << 2);
if (pi->mirror_regs)
pi->MPSC_CHR_2_m = v;
writel(v, pi->mpsc_base + MPSC_CHR_2);
return;
}
/*
******************************************************************************
*
* Driver Init Routines
*
******************************************************************************
*/
static void
mpsc_init_hw(struct mpsc_port_info *pi)
{
pr_debug("mpsc_init_hw[%d]: Initializing\n", pi->port.line);
mpsc_brg_init(pi, pi->brg_clk_src);
mpsc_brg_enable(pi);
mpsc_sdma_init(pi, dma_get_cache_alignment()); /* burst a cacheline */
mpsc_sdma_stop(pi);
mpsc_hw_init(pi);
return;
}
static int
mpsc_alloc_ring_mem(struct mpsc_port_info *pi)
{
int rc = 0;
pr_debug("mpsc_alloc_ring_mem[%d]: Allocating ring mem\n",
pi->port.line);
if (!pi->dma_region) {
if (!dma_supported(pi->port.dev, 0xffffffff)) {
printk(KERN_ERR "MPSC: Inadequate DMA support\n");
rc = -ENXIO;
}
else if ((pi->dma_region = dma_alloc_noncoherent(pi->port.dev,
MPSC_DMA_ALLOC_SIZE, &pi->dma_region_p, GFP_KERNEL))
== NULL) {
printk(KERN_ERR "MPSC: Can't alloc Desc region\n");
rc = -ENOMEM;
}
}
return rc;
}
static void
mpsc_free_ring_mem(struct mpsc_port_info *pi)
{
pr_debug("mpsc_free_ring_mem[%d]: Freeing ring mem\n", pi->port.line);
if (pi->dma_region) {
dma_free_noncoherent(pi->port.dev, MPSC_DMA_ALLOC_SIZE,
pi->dma_region, pi->dma_region_p);
pi->dma_region = NULL;
pi->dma_region_p = (dma_addr_t) NULL;
}
return;
}
static void
mpsc_init_rings(struct mpsc_port_info *pi)
{
struct mpsc_rx_desc *rxre;
struct mpsc_tx_desc *txre;
dma_addr_t dp, dp_p;
u8 *bp, *bp_p;
int i;
pr_debug("mpsc_init_rings[%d]: Initializing rings\n", pi->port.line);
BUG_ON(pi->dma_region == NULL);
memset(pi->dma_region, 0, MPSC_DMA_ALLOC_SIZE);
/*
* Descriptors & buffers are multiples of cacheline size and must be
* cacheline aligned.
*/
dp = ALIGN((u32) pi->dma_region, dma_get_cache_alignment());
dp_p = ALIGN((u32) pi->dma_region_p, dma_get_cache_alignment());
/*
* Partition dma region into rx ring descriptor, rx buffers,
* tx ring descriptors, and tx buffers.
*/
pi->rxr = dp;
pi->rxr_p = dp_p;
dp += MPSC_RXR_SIZE;
dp_p += MPSC_RXR_SIZE;
pi->rxb = (u8 *) dp;
pi->rxb_p = (u8 *) dp_p;
dp += MPSC_RXB_SIZE;
dp_p += MPSC_RXB_SIZE;
pi->rxr_posn = 0;
pi->txr = dp;
pi->txr_p = dp_p;
dp += MPSC_TXR_SIZE;
dp_p += MPSC_TXR_SIZE;
pi->txb = (u8 *) dp;
pi->txb_p = (u8 *) dp_p;
pi->txr_head = 0;
pi->txr_tail = 0;
/* Init rx ring descriptors */
dp = pi->rxr;
dp_p = pi->rxr_p;
bp = pi->rxb;
bp_p = pi->rxb_p;
for (i = 0; i < MPSC_RXR_ENTRIES; i++) {
rxre = (struct mpsc_rx_desc *)dp;
rxre->bufsize = cpu_to_be16(MPSC_RXBE_SIZE);
rxre->bytecnt = cpu_to_be16(0);
rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O |
SDMA_DESC_CMDSTAT_EI |
SDMA_DESC_CMDSTAT_F |
SDMA_DESC_CMDSTAT_L);
rxre->link = cpu_to_be32(dp_p + MPSC_RXRE_SIZE);
rxre->buf_ptr = cpu_to_be32(bp_p);
dp += MPSC_RXRE_SIZE;
dp_p += MPSC_RXRE_SIZE;
bp += MPSC_RXBE_SIZE;
bp_p += MPSC_RXBE_SIZE;
}
rxre->link = cpu_to_be32(pi->rxr_p); /* Wrap last back to first */
/* Init tx ring descriptors */
dp = pi->txr;
dp_p = pi->txr_p;
bp = pi->txb;
bp_p = pi->txb_p;
for (i = 0; i < MPSC_TXR_ENTRIES; i++) {
txre = (struct mpsc_tx_desc *)dp;
txre->link = cpu_to_be32(dp_p + MPSC_TXRE_SIZE);
txre->buf_ptr = cpu_to_be32(bp_p);
dp += MPSC_TXRE_SIZE;
dp_p += MPSC_TXRE_SIZE;
bp += MPSC_TXBE_SIZE;
bp_p += MPSC_TXBE_SIZE;
}
txre->link = cpu_to_be32(pi->txr_p); /* Wrap last back to first */
dma_cache_sync((void *) pi->dma_region, MPSC_DMA_ALLOC_SIZE,
DMA_BIDIRECTIONAL);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
flush_dcache_range((ulong)pi->dma_region,
(ulong)pi->dma_region + MPSC_DMA_ALLOC_SIZE);
#endif
return;
}
static void
mpsc_uninit_rings(struct mpsc_port_info *pi)
{
pr_debug("mpsc_uninit_rings[%d]: Uninitializing rings\n",pi->port.line);
BUG_ON(pi->dma_region == NULL);
pi->rxr = 0;
pi->rxr_p = 0;
pi->rxb = NULL;
pi->rxb_p = NULL;
pi->rxr_posn = 0;
pi->txr = 0;
pi->txr_p = 0;
pi->txb = NULL;
pi->txb_p = NULL;
pi->txr_head = 0;
pi->txr_tail = 0;
return;
}
static int
mpsc_make_ready(struct mpsc_port_info *pi)
{
int rc;
pr_debug("mpsc_make_ready[%d]: Making cltr ready\n", pi->port.line);
if (!pi->ready) {
mpsc_init_hw(pi);
if ((rc = mpsc_alloc_ring_mem(pi)))
return rc;
mpsc_init_rings(pi);
pi->ready = 1;
}
return 0;
}
/*
******************************************************************************
*
* Interrupt Handling Routines
*
******************************************************************************
*/
static inline int
mpsc_rx_intr(struct mpsc_port_info *pi)
{
struct mpsc_rx_desc *rxre;
struct tty_struct *tty = pi->port.info->tty;
u32 cmdstat, bytes_in, i;
int rc = 0;
u8 *bp;
char flag = TTY_NORMAL;
pr_debug("mpsc_rx_intr[%d]: Handling Rx intr\n", pi->port.line);
rxre = (struct mpsc_rx_desc *)(pi->rxr + (pi->rxr_posn*MPSC_RXRE_SIZE));
dma_cache_sync((void *)rxre, MPSC_RXRE_SIZE, DMA_FROM_DEVICE);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
invalidate_dcache_range((ulong)rxre,
(ulong)rxre + MPSC_RXRE_SIZE);
#endif
/*
* Loop through Rx descriptors handling ones that have been completed.
*/
while (!((cmdstat = be32_to_cpu(rxre->cmdstat)) & SDMA_DESC_CMDSTAT_O)){
bytes_in = be16_to_cpu(rxre->bytecnt);
/* Following use of tty struct directly is deprecated */
if (unlikely(tty_buffer_request_room(tty, bytes_in) < bytes_in)) {
if (tty->low_latency)
tty_flip_buffer_push(tty);
/*
* If this failed then we will throw away the bytes
* but must do so to clear interrupts.
*/
}
bp = pi->rxb + (pi->rxr_posn * MPSC_RXBE_SIZE);
dma_cache_sync((void *) bp, MPSC_RXBE_SIZE, DMA_FROM_DEVICE);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
invalidate_dcache_range((ulong)bp,
(ulong)bp + MPSC_RXBE_SIZE);
#endif
/*
* Other than for parity error, the manual provides little
* info on what data will be in a frame flagged by any of
* these errors. For parity error, it is the last byte in
* the buffer that had the error. As for the rest, I guess
* we'll assume there is no data in the buffer.
* If there is...it gets lost.
*/
if (unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR |
SDMA_DESC_CMDSTAT_FR | SDMA_DESC_CMDSTAT_OR))) {
pi->port.icount.rx++;
if (cmdstat & SDMA_DESC_CMDSTAT_BR) { /* Break */
pi->port.icount.brk++;
if (uart_handle_break(&pi->port))
goto next_frame;
}
else if (cmdstat & SDMA_DESC_CMDSTAT_FR)/* Framing */
pi->port.icount.frame++;
else if (cmdstat & SDMA_DESC_CMDSTAT_OR) /* Overrun */
pi->port.icount.overrun++;
cmdstat &= pi->port.read_status_mask;
if (cmdstat & SDMA_DESC_CMDSTAT_BR)
flag = TTY_BREAK;
else if (cmdstat & SDMA_DESC_CMDSTAT_FR)
flag = TTY_FRAME;
else if (cmdstat & SDMA_DESC_CMDSTAT_OR)
flag = TTY_OVERRUN;
else if (cmdstat & SDMA_DESC_CMDSTAT_PE)
flag = TTY_PARITY;
}
if (uart_handle_sysrq_char(&pi->port, *bp)) {
bp++;
bytes_in--;
goto next_frame;
}
if ((unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR |
SDMA_DESC_CMDSTAT_FR | SDMA_DESC_CMDSTAT_OR))) &&
!(cmdstat & pi->port.ignore_status_mask))
tty_insert_flip_char(tty, *bp, flag);
else {
for (i=0; i<bytes_in; i++)
tty_insert_flip_char(tty, *bp++, TTY_NORMAL);
pi->port.icount.rx += bytes_in;
}
next_frame:
rxre->bytecnt = cpu_to_be16(0);
wmb();
rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O |
SDMA_DESC_CMDSTAT_EI |
SDMA_DESC_CMDSTAT_F |
SDMA_DESC_CMDSTAT_L);
wmb();
dma_cache_sync((void *)rxre, MPSC_RXRE_SIZE, DMA_BIDIRECTIONAL);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
flush_dcache_range((ulong)rxre,
(ulong)rxre + MPSC_RXRE_SIZE);
#endif
/* Advance to next descriptor */
pi->rxr_posn = (pi->rxr_posn + 1) & (MPSC_RXR_ENTRIES - 1);
rxre = (struct mpsc_rx_desc *)(pi->rxr +
(pi->rxr_posn * MPSC_RXRE_SIZE));
dma_cache_sync((void *)rxre, MPSC_RXRE_SIZE, DMA_FROM_DEVICE);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
invalidate_dcache_range((ulong)rxre,
(ulong)rxre + MPSC_RXRE_SIZE);
#endif
rc = 1;
}
/* Restart rx engine, if its stopped */
if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
mpsc_start_rx(pi);
tty_flip_buffer_push(tty);
return rc;
}
static inline void
mpsc_setup_tx_desc(struct mpsc_port_info *pi, u32 count, u32 intr)
{
struct mpsc_tx_desc *txre;
txre = (struct mpsc_tx_desc *)(pi->txr +
(pi->txr_head * MPSC_TXRE_SIZE));
txre->bytecnt = cpu_to_be16(count);
txre->shadow = txre->bytecnt;
wmb(); /* ensure cmdstat is last field updated */
txre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O | SDMA_DESC_CMDSTAT_F |
SDMA_DESC_CMDSTAT_L | ((intr) ?
SDMA_DESC_CMDSTAT_EI
: 0));
wmb();
dma_cache_sync((void *) txre, MPSC_TXRE_SIZE, DMA_BIDIRECTIONAL);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
flush_dcache_range((ulong)txre,
(ulong)txre + MPSC_TXRE_SIZE);
#endif
return;
}
static inline void
mpsc_copy_tx_data(struct mpsc_port_info *pi)
{
struct circ_buf *xmit = &pi->port.info->xmit;
u8 *bp;
u32 i;
/* Make sure the desc ring isn't full */
while (CIRC_CNT(pi->txr_head, pi->txr_tail, MPSC_TXR_ENTRIES) <
(MPSC_TXR_ENTRIES - 1)) {
if (pi->port.x_char) {
/*
* Ideally, we should use the TCS field in
* CHR_1 to put the x_char out immediately but
* errata prevents us from being able to read
* CHR_2 to know that its safe to write to
* CHR_1. Instead, just put it in-band with
* all the other Tx data.
*/
bp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
*bp = pi->port.x_char;
pi->port.x_char = 0;
i = 1;
}
else if (!uart_circ_empty(xmit) && !uart_tx_stopped(&pi->port)){
i = min((u32) MPSC_TXBE_SIZE,
(u32) uart_circ_chars_pending(xmit));
i = min(i, (u32) CIRC_CNT_TO_END(xmit->head, xmit->tail,
UART_XMIT_SIZE));
bp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
memcpy(bp, &xmit->buf[xmit->tail], i);
xmit->tail = (xmit->tail + i) & (UART_XMIT_SIZE - 1);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&pi->port);
}
else /* All tx data copied into ring bufs */
return;
dma_cache_sync((void *) bp, MPSC_TXBE_SIZE, DMA_BIDIRECTIONAL);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
flush_dcache_range((ulong)bp,
(ulong)bp + MPSC_TXBE_SIZE);
#endif
mpsc_setup_tx_desc(pi, i, 1);
/* Advance to next descriptor */
pi->txr_head = (pi->txr_head + 1) & (MPSC_TXR_ENTRIES - 1);
}
return;
}
static inline int
mpsc_tx_intr(struct mpsc_port_info *pi)
{
struct mpsc_tx_desc *txre;
int rc = 0;
if (!mpsc_sdma_tx_active(pi)) {
txre = (struct mpsc_tx_desc *)(pi->txr +
(pi->txr_tail * MPSC_TXRE_SIZE));
dma_cache_sync((void *) txre, MPSC_TXRE_SIZE, DMA_FROM_DEVICE);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
invalidate_dcache_range((ulong)txre,
(ulong)txre + MPSC_TXRE_SIZE);
#endif
while (!(be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O)) {
rc = 1;
pi->port.icount.tx += be16_to_cpu(txre->bytecnt);
pi->txr_tail = (pi->txr_tail+1) & (MPSC_TXR_ENTRIES-1);
/* If no more data to tx, fall out of loop */
if (pi->txr_head == pi->txr_tail)
break;
txre = (struct mpsc_tx_desc *)(pi->txr +
(pi->txr_tail * MPSC_TXRE_SIZE));
dma_cache_sync((void *) txre, MPSC_TXRE_SIZE,
DMA_FROM_DEVICE);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
invalidate_dcache_range((ulong)txre,
(ulong)txre + MPSC_TXRE_SIZE);
#endif
}
mpsc_copy_tx_data(pi);
mpsc_sdma_start_tx(pi); /* start next desc if ready */
}
return rc;
}
/*
* This is the driver's interrupt handler. To avoid a race, we first clear
* the interrupt, then handle any completed Rx/Tx descriptors. When done
* handling those descriptors, we restart the Rx/Tx engines if they're stopped.
*/
static irqreturn_t
mpsc_sdma_intr(int irq, void *dev_id)
{
struct mpsc_port_info *pi = dev_id;
ulong iflags;
int rc = IRQ_NONE;
pr_debug("mpsc_sdma_intr[%d]: SDMA Interrupt Received\n",pi->port.line);
spin_lock_irqsave(&pi->port.lock, iflags);
mpsc_sdma_intr_ack(pi);
if (mpsc_rx_intr(pi))
rc = IRQ_HANDLED;
if (mpsc_tx_intr(pi))
rc = IRQ_HANDLED;
spin_unlock_irqrestore(&pi->port.lock, iflags);
pr_debug("mpsc_sdma_intr[%d]: SDMA Interrupt Handled\n", pi->port.line);
return rc;
}
/*
******************************************************************************
*
* serial_core.c Interface routines
*
******************************************************************************
*/
static uint
mpsc_tx_empty(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
ulong iflags;
uint rc;
spin_lock_irqsave(&pi->port.lock, iflags);
rc = mpsc_sdma_tx_active(pi) ? 0 : TIOCSER_TEMT;
spin_unlock_irqrestore(&pi->port.lock, iflags);
return rc;
}
static void
mpsc_set_mctrl(struct uart_port *port, uint mctrl)
{
/* Have no way to set modem control lines AFAICT */
return;
}
static uint
mpsc_get_mctrl(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
u32 mflags, status;
status = (pi->mirror_regs) ? pi->MPSC_CHR_10_m :
readl(pi->mpsc_base + MPSC_CHR_10);
mflags = 0;
if (status & 0x1)
mflags |= TIOCM_CTS;
if (status & 0x2)
mflags |= TIOCM_CAR;
return mflags | TIOCM_DSR; /* No way to tell if DSR asserted */
}
static void
mpsc_stop_tx(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
pr_debug("mpsc_stop_tx[%d]\n", port->line);
mpsc_freeze(pi);
return;
}
static void
mpsc_start_tx(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
mpsc_unfreeze(pi);
mpsc_copy_tx_data(pi);
mpsc_sdma_start_tx(pi);
pr_debug("mpsc_start_tx[%d]\n", port->line);
return;
}
static void
mpsc_start_rx(struct mpsc_port_info *pi)
{
pr_debug("mpsc_start_rx[%d]: Starting...\n", pi->port.line);
/* Issue a Receive Abort to clear any receive errors */
writel(MPSC_CHR_2_RA, pi->mpsc_base + MPSC_CHR_2);
if (pi->rcv_data) {
mpsc_enter_hunt(pi);
mpsc_sdma_cmd(pi, SDMA_SDCM_ERD);
}
return;
}
static void
mpsc_stop_rx(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
pr_debug("mpsc_stop_rx[%d]: Stopping...\n", port->line);
mpsc_sdma_cmd(pi, SDMA_SDCM_AR);
return;
}
static void
mpsc_enable_ms(struct uart_port *port)
{
return; /* Not supported */
}
static void
mpsc_break_ctl(struct uart_port *port, int ctl)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
ulong flags;
u32 v;
v = ctl ? 0x00ff0000 : 0;
spin_lock_irqsave(&pi->port.lock, flags);
if (pi->mirror_regs)
pi->MPSC_CHR_1_m = v;
writel(v, pi->mpsc_base + MPSC_CHR_1);
spin_unlock_irqrestore(&pi->port.lock, flags);
return;
}
static int
mpsc_startup(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
u32 flag = 0;
int rc;
pr_debug("mpsc_startup[%d]: Starting up MPSC, irq: %d\n",
port->line, pi->port.irq);
if ((rc = mpsc_make_ready(pi)) == 0) {
/* Setup IRQ handler */
mpsc_sdma_intr_ack(pi);
/* If irq's are shared, need to set flag */
if (mpsc_ports[0].port.irq == mpsc_ports[1].port.irq)
flag = IRQF_SHARED;
if (request_irq(pi->port.irq, mpsc_sdma_intr, flag,
"mpsc-sdma", pi))
printk(KERN_ERR "MPSC: Can't get SDMA IRQ %d\n",
pi->port.irq);
mpsc_sdma_intr_unmask(pi, 0xf);
mpsc_sdma_set_rx_ring(pi, (struct mpsc_rx_desc *)(pi->rxr_p +
(pi->rxr_posn * MPSC_RXRE_SIZE)));
}
return rc;
}
static void
mpsc_shutdown(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
pr_debug("mpsc_shutdown[%d]: Shutting down MPSC\n", port->line);
mpsc_sdma_stop(pi);
free_irq(pi->port.irq, pi);
return;
}
static void
mpsc_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
u32 baud;
ulong flags;
u32 chr_bits, stop_bits, par;
pi->c_iflag = termios->c_iflag;
pi->c_cflag = termios->c_cflag;
switch (termios->c_cflag & CSIZE) {
case CS5:
chr_bits = MPSC_MPCR_CL_5;
break;
case CS6:
chr_bits = MPSC_MPCR_CL_6;
break;
case CS7:
chr_bits = MPSC_MPCR_CL_7;
break;
case CS8:
default:
chr_bits = MPSC_MPCR_CL_8;
break;
}
if (termios->c_cflag & CSTOPB)
stop_bits = MPSC_MPCR_SBL_2;
else
stop_bits = MPSC_MPCR_SBL_1;
par = MPSC_CHR_2_PAR_EVEN;
if (termios->c_cflag & PARENB)
if (termios->c_cflag & PARODD)
par = MPSC_CHR_2_PAR_ODD;
#ifdef CMSPAR
if (termios->c_cflag & CMSPAR) {
if (termios->c_cflag & PARODD)
par = MPSC_CHR_2_PAR_MARK;
else
par = MPSC_CHR_2_PAR_SPACE;
}
#endif
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk);
spin_lock_irqsave(&pi->port.lock, flags);
uart_update_timeout(port, termios->c_cflag, baud);
mpsc_set_char_length(pi, chr_bits);
mpsc_set_stop_bit_length(pi, stop_bits);
mpsc_set_parity(pi, par);
mpsc_set_baudrate(pi, baud);
/* Characters/events to read */
pi->rcv_data = 1;
pi->port.read_status_mask = SDMA_DESC_CMDSTAT_OR;
if (termios->c_iflag & INPCK)
pi->port.read_status_mask |= SDMA_DESC_CMDSTAT_PE |
SDMA_DESC_CMDSTAT_FR;
if (termios->c_iflag & (BRKINT | PARMRK))
pi->port.read_status_mask |= SDMA_DESC_CMDSTAT_BR;
/* Characters/events to ignore */
pi->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_PE |
SDMA_DESC_CMDSTAT_FR;
if (termios->c_iflag & IGNBRK) {
pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_BR;
if (termios->c_iflag & IGNPAR)
pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_OR;
}
/* Ignore all chars if CREAD not set */
if (!(termios->c_cflag & CREAD))
pi->rcv_data = 0;
else
mpsc_start_rx(pi);
spin_unlock_irqrestore(&pi->port.lock, flags);
return;
}
static const char *
mpsc_type(struct uart_port *port)
{
pr_debug("mpsc_type[%d]: port type: %s\n", port->line,MPSC_DRIVER_NAME);
return MPSC_DRIVER_NAME;
}
static int
mpsc_request_port(struct uart_port *port)
{
/* Should make chip/platform specific call */
return 0;
}
static void
mpsc_release_port(struct uart_port *port)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
if (pi->ready) {
mpsc_uninit_rings(pi);
mpsc_free_ring_mem(pi);
pi->ready = 0;
}
return;
}
static void
mpsc_config_port(struct uart_port *port, int flags)
{
return;
}
static int
mpsc_verify_port(struct uart_port *port, struct serial_struct *ser)
{
struct mpsc_port_info *pi = (struct mpsc_port_info *)port;
int rc = 0;
pr_debug("mpsc_verify_port[%d]: Verifying port data\n", pi->port.line);
if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPSC)
rc = -EINVAL;
else if (pi->port.irq != ser->irq)
rc = -EINVAL;
else if (ser->io_type != SERIAL_IO_MEM)
rc = -EINVAL;
else if (pi->port.uartclk / 16 != ser->baud_base) /* Not sure */
rc = -EINVAL;
else if ((void *)pi->port.mapbase != ser->iomem_base)
rc = -EINVAL;
else if (pi->port.iobase != ser->port)
rc = -EINVAL;
else if (ser->hub6 != 0)
rc = -EINVAL;
return rc;
}
static struct uart_ops mpsc_pops = {
.tx_empty = mpsc_tx_empty,
.set_mctrl = mpsc_set_mctrl,
.get_mctrl = mpsc_get_mctrl,
.stop_tx = mpsc_stop_tx,
.start_tx = mpsc_start_tx,
.stop_rx = mpsc_stop_rx,
.enable_ms = mpsc_enable_ms,
.break_ctl = mpsc_break_ctl,
.startup = mpsc_startup,
.shutdown = mpsc_shutdown,
.set_termios = mpsc_set_termios,
.type = mpsc_type,
.release_port = mpsc_release_port,
.request_port = mpsc_request_port,
.config_port = mpsc_config_port,
.verify_port = mpsc_verify_port,
};
/*
******************************************************************************
*
* Console Interface Routines
*
******************************************************************************
*/
#ifdef CONFIG_SERIAL_MPSC_CONSOLE
static void
mpsc_console_write(struct console *co, const char *s, uint count)
{
struct mpsc_port_info *pi = &mpsc_ports[co->index];
u8 *bp, *dp, add_cr = 0;
int i;
while (mpsc_sdma_tx_active(pi))
udelay(100);
while (count > 0) {
bp = dp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
for (i = 0; i < MPSC_TXBE_SIZE; i++) {
if (count == 0)
break;
if (add_cr) {
*(dp++) = '\r';
add_cr = 0;
}
else {
*(dp++) = *s;
if (*(s++) == '\n') { /* add '\r' after '\n' */
add_cr = 1;
count++;
}
}
count--;
}
dma_cache_sync((void *) bp, MPSC_TXBE_SIZE, DMA_BIDIRECTIONAL);
#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
flush_dcache_range((ulong)bp,
(ulong)bp + MPSC_TXBE_SIZE);
#endif
mpsc_setup_tx_desc(pi, i, 0);
pi->txr_head = (pi->txr_head + 1) & (MPSC_TXR_ENTRIES - 1);
mpsc_sdma_start_tx(pi);
while (mpsc_sdma_tx_active(pi))
udelay(100);
pi->txr_tail = (pi->txr_tail + 1) & (MPSC_TXR_ENTRIES - 1);
}
return;
}
static int __init
mpsc_console_setup(struct console *co, char *options)
{
struct mpsc_port_info *pi;
int baud, bits, parity, flow;
pr_debug("mpsc_console_setup[%d]: options: %s\n", co->index, options);
if (co->index >= MPSC_NUM_CTLRS)
co->index = 0;
pi = &mpsc_ports[co->index];
baud = pi->default_baud;
bits = pi->default_bits;
parity = pi->default_parity;
flow = pi->default_flow;
if (!pi->port.ops)
return -ENODEV;
spin_lock_init(&pi->port.lock); /* Temporary fix--copied from 8250.c */
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(&pi->port, co, baud, parity, bits, flow);
}
static struct console mpsc_console = {
.name = MPSC_DEV_NAME,
.write = mpsc_console_write,
.device = uart_console_device,
.setup = mpsc_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &mpsc_reg,
};
static int __init
mpsc_late_console_init(void)
{
pr_debug("mpsc_late_console_init: Enter\n");
if (!(mpsc_console.flags & CON_ENABLED))
register_console(&mpsc_console);
return 0;
}
late_initcall(mpsc_late_console_init);
#define MPSC_CONSOLE &mpsc_console
#else
#define MPSC_CONSOLE NULL
#endif
/*
******************************************************************************
*
* Dummy Platform Driver to extract & map shared register regions
*
******************************************************************************
*/
static void
mpsc_resource_err(char *s)
{
printk(KERN_WARNING "MPSC: Platform device resource error in %s\n", s);
return;
}
static int
mpsc_shared_map_regs(struct platform_device *pd)
{
struct resource *r;
if ((r = platform_get_resource(pd, IORESOURCE_MEM,
MPSC_ROUTING_BASE_ORDER)) && request_mem_region(r->start,
MPSC_ROUTING_REG_BLOCK_SIZE, "mpsc_routing_regs")) {
mpsc_shared_regs.mpsc_routing_base = ioremap(r->start,
MPSC_ROUTING_REG_BLOCK_SIZE);
mpsc_shared_regs.mpsc_routing_base_p = r->start;
}
else {
mpsc_resource_err("MPSC routing base");
return -ENOMEM;
}
if ((r = platform_get_resource(pd, IORESOURCE_MEM,
MPSC_SDMA_INTR_BASE_ORDER)) && request_mem_region(r->start,
MPSC_SDMA_INTR_REG_BLOCK_SIZE, "sdma_intr_regs")) {
mpsc_shared_regs.sdma_intr_base = ioremap(r->start,
MPSC_SDMA_INTR_REG_BLOCK_SIZE);
mpsc_shared_regs.sdma_intr_base_p = r->start;
}
else {
iounmap(mpsc_shared_regs.mpsc_routing_base);
release_mem_region(mpsc_shared_regs.mpsc_routing_base_p,
MPSC_ROUTING_REG_BLOCK_SIZE);
mpsc_resource_err("SDMA intr base");
return -ENOMEM;
}
return 0;
}
static void
mpsc_shared_unmap_regs(void)
{
if (!mpsc_shared_regs.mpsc_routing_base) {
iounmap(mpsc_shared_regs.mpsc_routing_base);
release_mem_region(mpsc_shared_regs.mpsc_routing_base_p,
MPSC_ROUTING_REG_BLOCK_SIZE);
}
if (!mpsc_shared_regs.sdma_intr_base) {
iounmap(mpsc_shared_regs.sdma_intr_base);
release_mem_region(mpsc_shared_regs.sdma_intr_base_p,
MPSC_SDMA_INTR_REG_BLOCK_SIZE);
}
mpsc_shared_regs.mpsc_routing_base = NULL;
mpsc_shared_regs.sdma_intr_base = NULL;
mpsc_shared_regs.mpsc_routing_base_p = 0;
mpsc_shared_regs.sdma_intr_base_p = 0;
return;
}
static int
mpsc_shared_drv_probe(struct platform_device *dev)
{
struct mpsc_shared_pdata *pdata;
int rc = -ENODEV;
if (dev->id == 0) {
if (!(rc = mpsc_shared_map_regs(dev))) {
pdata = (struct mpsc_shared_pdata *)dev->dev.platform_data;
mpsc_shared_regs.MPSC_MRR_m = pdata->mrr_val;
mpsc_shared_regs.MPSC_RCRR_m= pdata->rcrr_val;
mpsc_shared_regs.MPSC_TCRR_m= pdata->tcrr_val;
mpsc_shared_regs.SDMA_INTR_CAUSE_m =
pdata->intr_cause_val;
mpsc_shared_regs.SDMA_INTR_MASK_m =
pdata->intr_mask_val;
rc = 0;
}
}
return rc;
}
static int
mpsc_shared_drv_remove(struct platform_device *dev)
{
int rc = -ENODEV;
if (dev->id == 0) {
mpsc_shared_unmap_regs();
mpsc_shared_regs.MPSC_MRR_m = 0;
mpsc_shared_regs.MPSC_RCRR_m = 0;
mpsc_shared_regs.MPSC_TCRR_m = 0;
mpsc_shared_regs.SDMA_INTR_CAUSE_m = 0;
mpsc_shared_regs.SDMA_INTR_MASK_m = 0;
rc = 0;
}
return rc;
}
static struct platform_driver mpsc_shared_driver = {
.probe = mpsc_shared_drv_probe,
.remove = mpsc_shared_drv_remove,
.driver = {
.name = MPSC_SHARED_NAME,
},
};
/*
******************************************************************************
*
* Driver Interface Routines
*
******************************************************************************
*/
static struct uart_driver mpsc_reg = {
.owner = THIS_MODULE,
.driver_name = MPSC_DRIVER_NAME,
.dev_name = MPSC_DEV_NAME,
.major = MPSC_MAJOR,
.minor = MPSC_MINOR_START,
.nr = MPSC_NUM_CTLRS,
.cons = MPSC_CONSOLE,
};
static int
mpsc_drv_map_regs(struct mpsc_port_info *pi, struct platform_device *pd)
{
struct resource *r;
if ((r = platform_get_resource(pd, IORESOURCE_MEM, MPSC_BASE_ORDER)) &&
request_mem_region(r->start, MPSC_REG_BLOCK_SIZE, "mpsc_regs")){
pi->mpsc_base = ioremap(r->start, MPSC_REG_BLOCK_SIZE);
pi->mpsc_base_p = r->start;
}
else {
mpsc_resource_err("MPSC base");
return -ENOMEM;
}
if ((r = platform_get_resource(pd, IORESOURCE_MEM,
MPSC_SDMA_BASE_ORDER)) && request_mem_region(r->start,
MPSC_SDMA_REG_BLOCK_SIZE, "sdma_regs")) {
pi->sdma_base = ioremap(r->start,MPSC_SDMA_REG_BLOCK_SIZE);
pi->sdma_base_p = r->start;
}
else {
mpsc_resource_err("SDMA base");
if (pi->mpsc_base) {
iounmap(pi->mpsc_base);
pi->mpsc_base = NULL;
}
return -ENOMEM;
}
if ((r = platform_get_resource(pd,IORESOURCE_MEM,MPSC_BRG_BASE_ORDER))
&& request_mem_region(r->start, MPSC_BRG_REG_BLOCK_SIZE,
"brg_regs")) {
pi->brg_base = ioremap(r->start, MPSC_BRG_REG_BLOCK_SIZE);
pi->brg_base_p = r->start;
}
else {
mpsc_resource_err("BRG base");
if (pi->mpsc_base) {
iounmap(pi->mpsc_base);
pi->mpsc_base = NULL;
}
if (pi->sdma_base) {
iounmap(pi->sdma_base);
pi->sdma_base = NULL;
}
return -ENOMEM;
}
return 0;
}
static void
mpsc_drv_unmap_regs(struct mpsc_port_info *pi)
{
if (!pi->mpsc_base) {
iounmap(pi->mpsc_base);
release_mem_region(pi->mpsc_base_p, MPSC_REG_BLOCK_SIZE);
}
if (!pi->sdma_base) {
iounmap(pi->sdma_base);
release_mem_region(pi->sdma_base_p, MPSC_SDMA_REG_BLOCK_SIZE);
}
if (!pi->brg_base) {
iounmap(pi->brg_base);
release_mem_region(pi->brg_base_p, MPSC_BRG_REG_BLOCK_SIZE);
}
pi->mpsc_base = NULL;
pi->sdma_base = NULL;
pi->brg_base = NULL;
pi->mpsc_base_p = 0;
pi->sdma_base_p = 0;
pi->brg_base_p = 0;
return;
}
static void
mpsc_drv_get_platform_data(struct mpsc_port_info *pi,
struct platform_device *pd, int num)
{
struct mpsc_pdata *pdata;
pdata = (struct mpsc_pdata *)pd->dev.platform_data;
pi->port.uartclk = pdata->brg_clk_freq;
pi->port.iotype = UPIO_MEM;
pi->port.line = num;
pi->port.type = PORT_MPSC;
pi->port.fifosize = MPSC_TXBE_SIZE;
pi->port.membase = pi->mpsc_base;
pi->port.mapbase = (ulong)pi->mpsc_base;
pi->port.ops = &mpsc_pops;
pi->mirror_regs = pdata->mirror_regs;
pi->cache_mgmt = pdata->cache_mgmt;
pi->brg_can_tune = pdata->brg_can_tune;
pi->brg_clk_src = pdata->brg_clk_src;
pi->mpsc_max_idle = pdata->max_idle;
pi->default_baud = pdata->default_baud;
pi->default_bits = pdata->default_bits;
pi->default_parity = pdata->default_parity;
pi->default_flow = pdata->default_flow;
/* Initial values of mirrored regs */
pi->MPSC_CHR_1_m = pdata->chr_1_val;
pi->MPSC_CHR_2_m = pdata->chr_2_val;
pi->MPSC_CHR_10_m = pdata->chr_10_val;
pi->MPSC_MPCR_m = pdata->mpcr_val;
pi->BRG_BCR_m = pdata->bcr_val;
pi->shared_regs = &mpsc_shared_regs;
pi->port.irq = platform_get_irq(pd, 0);
return;
}
static int
mpsc_drv_probe(struct platform_device *dev)
{
struct mpsc_port_info *pi;
int rc = -ENODEV;
pr_debug("mpsc_drv_probe: Adding MPSC %d\n", dev->id);
if (dev->id < MPSC_NUM_CTLRS) {
pi = &mpsc_ports[dev->id];
if (!(rc = mpsc_drv_map_regs(pi, dev))) {
mpsc_drv_get_platform_data(pi, dev, dev->id);
if (!(rc = mpsc_make_ready(pi)))
if (!(rc = uart_add_one_port(&mpsc_reg,
&pi->port)))
rc = 0;
else {
mpsc_release_port(
(struct uart_port *)pi);
mpsc_drv_unmap_regs(pi);
}
else
mpsc_drv_unmap_regs(pi);
}
}
return rc;
}
static int
mpsc_drv_remove(struct platform_device *dev)
{
pr_debug("mpsc_drv_exit: Removing MPSC %d\n", dev->id);
if (dev->id < MPSC_NUM_CTLRS) {
uart_remove_one_port(&mpsc_reg, &mpsc_ports[dev->id].port);
mpsc_release_port((struct uart_port *)&mpsc_ports[dev->id].port);
mpsc_drv_unmap_regs(&mpsc_ports[dev->id]);
return 0;
}
else
return -ENODEV;
}
static struct platform_driver mpsc_driver = {
.probe = mpsc_drv_probe,
.remove = mpsc_drv_remove,
.driver = {
.name = MPSC_CTLR_NAME,
},
};
static int __init
mpsc_drv_init(void)
{
int rc;
printk(KERN_INFO "Serial: MPSC driver $Revision: 1.00 $\n");
memset(mpsc_ports, 0, sizeof(mpsc_ports));
memset(&mpsc_shared_regs, 0, sizeof(mpsc_shared_regs));
if (!(rc = uart_register_driver(&mpsc_reg))) {
if (!(rc = platform_driver_register(&mpsc_shared_driver))) {
if ((rc = platform_driver_register(&mpsc_driver))) {
platform_driver_unregister(&mpsc_shared_driver);
uart_unregister_driver(&mpsc_reg);
}
}
else
uart_unregister_driver(&mpsc_reg);
}
return rc;
}
static void __exit
mpsc_drv_exit(void)
{
platform_driver_unregister(&mpsc_driver);
platform_driver_unregister(&mpsc_shared_driver);
uart_unregister_driver(&mpsc_reg);
memset(mpsc_ports, 0, sizeof(mpsc_ports));
memset(&mpsc_shared_regs, 0, sizeof(mpsc_shared_regs));
return;
}
module_init(mpsc_drv_init);
module_exit(mpsc_drv_exit);
MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
MODULE_DESCRIPTION("Generic Marvell MPSC serial/UART driver $Revision: 1.00 $");
MODULE_VERSION(MPSC_VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS_CHARDEV_MAJOR(MPSC_MAJOR);
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