linux/drivers/tty/serial/qcom_geni_serial.c
Krzysztof Kozlowski 5f949f140f serial: qcom-geni: fix enabling deactivated interrupt
The driver have a race, experienced only with PREEMPT_RT patchset:

CPU0                         | CPU1
==================================================================
qcom_geni_serial_probe       |
  uart_add_one_port          |
                             | serdev_drv_probe
                             |   qca_serdev_probe
                             |     serdev_device_open
                             |       uart_open
                             |         uart_startup
                             |           qcom_geni_serial_startup
                             |             enable_irq
                             |               __irq_startup
                             |                 WARN_ON()
                             |                 IRQ not activated
  request_threaded_irq       |
    irq_domain_activate_irq  |

The warning:

  894000.serial: ttyHS1 at MMIO 0x894000 (irq = 144, base_baud = 0) is a MSM
  serial serial0: tty port ttyHS1 registered
  WARNING: CPU: 7 PID: 107 at kernel/irq/chip.c:241 __irq_startup+0x78/0xd8
  ...
  qcom_geni_serial 894000.serial: serial engine reports 0 RX bytes in!

Adding UART port triggers probe of child serial devices - serdev and
eventually Qualcomm Bluetooth hci_qca driver.  This opens UART port
which enables the interrupt before it got activated in
request_threaded_irq().  The issue originates in commit f3974413cf
("tty: serial: qcom_geni_serial: Wakeup IRQ cleanup") and discussion on
mailing list [1].  However the above commit does not explain why the
uart_add_one_port() is moved above requesting interrupt.

[1] https://lore.kernel.org/all/5d9f3dfa.1c69fb81.84c4b.30bf@mx.google.com/

Fixes: f3974413cf ("tty: serial: qcom_geni_serial: Wakeup IRQ cleanup")
Cc: <stable@vger.kernel.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20230505152301.2181270-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13 20:00:54 +09:00

1851 lines
49 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
/* Disable MMIO tracing to prevent excessive logging of unwanted MMIO traces */
#define __DISABLE_TRACE_MMIO__
#include <linux/clk.h>
#include <linux/console.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pm_opp.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/pm_wakeirq.h>
#include <linux/soc/qcom/geni-se.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <dt-bindings/interconnect/qcom,icc.h>
/* UART specific GENI registers */
#define SE_UART_LOOPBACK_CFG 0x22c
#define SE_UART_IO_MACRO_CTRL 0x240
#define SE_UART_TX_TRANS_CFG 0x25c
#define SE_UART_TX_WORD_LEN 0x268
#define SE_UART_TX_STOP_BIT_LEN 0x26c
#define SE_UART_TX_TRANS_LEN 0x270
#define SE_UART_RX_TRANS_CFG 0x280
#define SE_UART_RX_WORD_LEN 0x28c
#define SE_UART_RX_STALE_CNT 0x294
#define SE_UART_TX_PARITY_CFG 0x2a4
#define SE_UART_RX_PARITY_CFG 0x2a8
#define SE_UART_MANUAL_RFR 0x2ac
/* SE_UART_TRANS_CFG */
#define UART_TX_PAR_EN BIT(0)
#define UART_CTS_MASK BIT(1)
/* SE_UART_TX_STOP_BIT_LEN */
#define TX_STOP_BIT_LEN_1 0
#define TX_STOP_BIT_LEN_2 2
/* SE_UART_RX_TRANS_CFG */
#define UART_RX_PAR_EN BIT(3)
/* SE_UART_RX_WORD_LEN */
#define RX_WORD_LEN_MASK GENMASK(9, 0)
/* SE_UART_RX_STALE_CNT */
#define RX_STALE_CNT GENMASK(23, 0)
/* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */
#define PAR_CALC_EN BIT(0)
#define PAR_EVEN 0x00
#define PAR_ODD 0x01
#define PAR_SPACE 0x10
/* SE_UART_MANUAL_RFR register fields */
#define UART_MANUAL_RFR_EN BIT(31)
#define UART_RFR_NOT_READY BIT(1)
#define UART_RFR_READY BIT(0)
/* UART M_CMD OP codes */
#define UART_START_TX 0x1
/* UART S_CMD OP codes */
#define UART_START_READ 0x1
#define UART_PARAM 0x1
#define UART_PARAM_RFR_OPEN BIT(7)
#define UART_OVERSAMPLING 32
#define STALE_TIMEOUT 16
#define DEFAULT_BITS_PER_CHAR 10
#define GENI_UART_CONS_PORTS 1
#define GENI_UART_PORTS 3
#define DEF_FIFO_DEPTH_WORDS 16
#define DEF_TX_WM 2
#define DEF_FIFO_WIDTH_BITS 32
#define UART_RX_WM 2
/* SE_UART_LOOPBACK_CFG */
#define RX_TX_SORTED BIT(0)
#define CTS_RTS_SORTED BIT(1)
#define RX_TX_CTS_RTS_SORTED (RX_TX_SORTED | CTS_RTS_SORTED)
/* UART pin swap value */
#define DEFAULT_IO_MACRO_IO0_IO1_MASK GENMASK(3, 0)
#define IO_MACRO_IO0_SEL 0x3
#define DEFAULT_IO_MACRO_IO2_IO3_MASK GENMASK(15, 4)
#define IO_MACRO_IO2_IO3_SWAP 0x4640
/* We always configure 4 bytes per FIFO word */
#define BYTES_PER_FIFO_WORD 4U
#define DMA_RX_BUF_SIZE 2048
struct qcom_geni_device_data {
bool console;
enum geni_se_xfer_mode mode;
};
struct qcom_geni_private_data {
/* NOTE: earlycon port will have NULL here */
struct uart_driver *drv;
u32 poll_cached_bytes;
unsigned int poll_cached_bytes_cnt;
u32 write_cached_bytes;
unsigned int write_cached_bytes_cnt;
};
struct qcom_geni_serial_port {
struct uart_port uport;
struct geni_se se;
const char *name;
u32 tx_fifo_depth;
u32 tx_fifo_width;
u32 rx_fifo_depth;
dma_addr_t tx_dma_addr;
dma_addr_t rx_dma_addr;
bool setup;
unsigned int baud;
void *rx_buf;
u32 loopback;
bool brk;
unsigned int tx_remaining;
int wakeup_irq;
bool rx_tx_swap;
bool cts_rts_swap;
struct qcom_geni_private_data private_data;
const struct qcom_geni_device_data *dev_data;
};
static const struct uart_ops qcom_geni_console_pops;
static const struct uart_ops qcom_geni_uart_pops;
static struct uart_driver qcom_geni_console_driver;
static struct uart_driver qcom_geni_uart_driver;
static inline struct qcom_geni_serial_port *to_dev_port(struct uart_port *uport)
{
return container_of(uport, struct qcom_geni_serial_port, uport);
}
static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = {
[0] = {
.uport = {
.iotype = UPIO_MEM,
.ops = &qcom_geni_uart_pops,
.flags = UPF_BOOT_AUTOCONF,
.line = 0,
},
},
[1] = {
.uport = {
.iotype = UPIO_MEM,
.ops = &qcom_geni_uart_pops,
.flags = UPF_BOOT_AUTOCONF,
.line = 1,
},
},
[2] = {
.uport = {
.iotype = UPIO_MEM,
.ops = &qcom_geni_uart_pops,
.flags = UPF_BOOT_AUTOCONF,
.line = 2,
},
},
};
static struct qcom_geni_serial_port qcom_geni_console_port = {
.uport = {
.iotype = UPIO_MEM,
.ops = &qcom_geni_console_pops,
.flags = UPF_BOOT_AUTOCONF,
.line = 0,
},
};
static int qcom_geni_serial_request_port(struct uart_port *uport)
{
struct platform_device *pdev = to_platform_device(uport->dev);
struct qcom_geni_serial_port *port = to_dev_port(uport);
uport->membase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(uport->membase))
return PTR_ERR(uport->membase);
port->se.base = uport->membase;
return 0;
}
static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
{
if (cfg_flags & UART_CONFIG_TYPE) {
uport->type = PORT_MSM;
qcom_geni_serial_request_port(uport);
}
}
static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport)
{
unsigned int mctrl = TIOCM_DSR | TIOCM_CAR;
u32 geni_ios;
if (uart_console(uport)) {
mctrl |= TIOCM_CTS;
} else {
geni_ios = readl(uport->membase + SE_GENI_IOS);
if (!(geni_ios & IO2_DATA_IN))
mctrl |= TIOCM_CTS;
}
return mctrl;
}
static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
unsigned int mctrl)
{
u32 uart_manual_rfr = 0;
struct qcom_geni_serial_port *port = to_dev_port(uport);
if (uart_console(uport))
return;
if (mctrl & TIOCM_LOOP)
port->loopback = RX_TX_CTS_RTS_SORTED;
if (!(mctrl & TIOCM_RTS) && !uport->suspended)
uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
}
static const char *qcom_geni_serial_get_type(struct uart_port *uport)
{
return "MSM";
}
static struct qcom_geni_serial_port *get_port_from_line(int line, bool console)
{
struct qcom_geni_serial_port *port;
int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS;
if (line < 0 || line >= nr_ports)
return ERR_PTR(-ENXIO);
port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line];
return port;
}
static bool qcom_geni_serial_main_active(struct uart_port *uport)
{
return readl(uport->membase + SE_GENI_STATUS) & M_GENI_CMD_ACTIVE;
}
static bool qcom_geni_serial_secondary_active(struct uart_port *uport)
{
return readl(uport->membase + SE_GENI_STATUS) & S_GENI_CMD_ACTIVE;
}
static bool qcom_geni_serial_poll_bit(struct uart_port *uport,
int offset, int field, bool set)
{
u32 reg;
struct qcom_geni_serial_port *port;
unsigned int baud;
unsigned int fifo_bits;
unsigned long timeout_us = 20000;
struct qcom_geni_private_data *private_data = uport->private_data;
if (private_data->drv) {
port = to_dev_port(uport);
baud = port->baud;
if (!baud)
baud = 115200;
fifo_bits = port->tx_fifo_depth * port->tx_fifo_width;
/*
* Total polling iterations based on FIFO worth of bytes to be
* sent at current baud. Add a little fluff to the wait.
*/
timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
}
/*
* Use custom implementation instead of readl_poll_atomic since ktimer
* is not ready at the time of early console.
*/
timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
while (timeout_us) {
reg = readl(uport->membase + offset);
if ((bool)(reg & field) == set)
return true;
udelay(10);
timeout_us -= 10;
}
return false;
}
static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size)
{
u32 m_cmd;
writel(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN);
m_cmd = UART_START_TX << M_OPCODE_SHFT;
writel(m_cmd, uport->membase + SE_GENI_M_CMD0);
}
static void qcom_geni_serial_poll_tx_done(struct uart_port *uport)
{
int done;
u32 irq_clear = M_CMD_DONE_EN;
done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_DONE_EN, true);
if (!done) {
writel(M_GENI_CMD_ABORT, uport->membase +
SE_GENI_M_CMD_CTRL_REG);
irq_clear |= M_CMD_ABORT_EN;
qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_ABORT_EN, true);
}
writel(irq_clear, uport->membase + SE_GENI_M_IRQ_CLEAR);
}
static void qcom_geni_serial_abort_rx(struct uart_port *uport)
{
u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG);
qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
S_GENI_CMD_ABORT, false);
writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
writel(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG);
}
#ifdef CONFIG_CONSOLE_POLL
static int qcom_geni_serial_get_char(struct uart_port *uport)
{
struct qcom_geni_private_data *private_data = uport->private_data;
u32 status;
u32 word_cnt;
int ret;
if (!private_data->poll_cached_bytes_cnt) {
status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
writel(status, uport->membase + SE_GENI_M_IRQ_CLEAR);
status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
writel(status, uport->membase + SE_GENI_S_IRQ_CLEAR);
status = readl(uport->membase + SE_GENI_RX_FIFO_STATUS);
word_cnt = status & RX_FIFO_WC_MSK;
if (!word_cnt)
return NO_POLL_CHAR;
if (word_cnt == 1 && (status & RX_LAST))
/*
* NOTE: If RX_LAST_BYTE_VALID is 0 it needs to be
* treated as if it was BYTES_PER_FIFO_WORD.
*/
private_data->poll_cached_bytes_cnt =
(status & RX_LAST_BYTE_VALID_MSK) >>
RX_LAST_BYTE_VALID_SHFT;
if (private_data->poll_cached_bytes_cnt == 0)
private_data->poll_cached_bytes_cnt = BYTES_PER_FIFO_WORD;
private_data->poll_cached_bytes =
readl(uport->membase + SE_GENI_RX_FIFOn);
}
private_data->poll_cached_bytes_cnt--;
ret = private_data->poll_cached_bytes & 0xff;
private_data->poll_cached_bytes >>= 8;
return ret;
}
static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
unsigned char c)
{
writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
qcom_geni_serial_setup_tx(uport, 1);
WARN_ON(!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_TX_FIFO_WATERMARK_EN, true));
writel(c, uport->membase + SE_GENI_TX_FIFOn);
writel(M_TX_FIFO_WATERMARK_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
qcom_geni_serial_poll_tx_done(uport);
}
#endif
#ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
static void qcom_geni_serial_wr_char(struct uart_port *uport, unsigned char ch)
{
struct qcom_geni_private_data *private_data = uport->private_data;
private_data->write_cached_bytes =
(private_data->write_cached_bytes >> 8) | (ch << 24);
private_data->write_cached_bytes_cnt++;
if (private_data->write_cached_bytes_cnt == BYTES_PER_FIFO_WORD) {
writel(private_data->write_cached_bytes,
uport->membase + SE_GENI_TX_FIFOn);
private_data->write_cached_bytes_cnt = 0;
}
}
static void
__qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
unsigned int count)
{
struct qcom_geni_private_data *private_data = uport->private_data;
int i;
u32 bytes_to_send = count;
for (i = 0; i < count; i++) {
/*
* uart_console_write() adds a carriage return for each newline.
* Account for additional bytes to be written.
*/
if (s[i] == '\n')
bytes_to_send++;
}
writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
qcom_geni_serial_setup_tx(uport, bytes_to_send);
for (i = 0; i < count; ) {
size_t chars_to_write = 0;
size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM;
/*
* If the WM bit never set, then the Tx state machine is not
* in a valid state, so break, cancel/abort any existing
* command. Unfortunately the current data being written is
* lost.
*/
if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_TX_FIFO_WATERMARK_EN, true))
break;
chars_to_write = min_t(size_t, count - i, avail / 2);
uart_console_write(uport, s + i, chars_to_write,
qcom_geni_serial_wr_char);
writel(M_TX_FIFO_WATERMARK_EN, uport->membase +
SE_GENI_M_IRQ_CLEAR);
i += chars_to_write;
}
if (private_data->write_cached_bytes_cnt) {
private_data->write_cached_bytes >>= BITS_PER_BYTE *
(BYTES_PER_FIFO_WORD - private_data->write_cached_bytes_cnt);
writel(private_data->write_cached_bytes,
uport->membase + SE_GENI_TX_FIFOn);
private_data->write_cached_bytes_cnt = 0;
}
qcom_geni_serial_poll_tx_done(uport);
}
static void qcom_geni_serial_console_write(struct console *co, const char *s,
unsigned int count)
{
struct uart_port *uport;
struct qcom_geni_serial_port *port;
bool locked = true;
unsigned long flags;
u32 geni_status;
u32 irq_en;
WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS);
port = get_port_from_line(co->index, true);
if (IS_ERR(port))
return;
uport = &port->uport;
if (oops_in_progress)
locked = spin_trylock_irqsave(&uport->lock, flags);
else
spin_lock_irqsave(&uport->lock, flags);
geni_status = readl(uport->membase + SE_GENI_STATUS);
/* Cancel the current write to log the fault */
if (!locked) {
geni_se_cancel_m_cmd(&port->se);
if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_CANCEL_EN, true)) {
geni_se_abort_m_cmd(&port->se);
qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_ABORT_EN, true);
writel(M_CMD_ABORT_EN, uport->membase +
SE_GENI_M_IRQ_CLEAR);
}
writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
} else if ((geni_status & M_GENI_CMD_ACTIVE) && !port->tx_remaining) {
/*
* It seems we can't interrupt existing transfers if all data
* has been sent, in which case we need to look for done first.
*/
qcom_geni_serial_poll_tx_done(uport);
if (!uart_circ_empty(&uport->state->xmit)) {
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
writel(irq_en | M_TX_FIFO_WATERMARK_EN,
uport->membase + SE_GENI_M_IRQ_EN);
}
}
__qcom_geni_serial_console_write(uport, s, count);
if (port->tx_remaining)
qcom_geni_serial_setup_tx(uport, port->tx_remaining);
if (locked)
spin_unlock_irqrestore(&uport->lock, flags);
}
static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
{
u32 i;
unsigned char buf[sizeof(u32)];
struct tty_port *tport;
struct qcom_geni_serial_port *port = to_dev_port(uport);
tport = &uport->state->port;
for (i = 0; i < bytes; ) {
int c;
int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);
ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
i += chunk;
if (drop)
continue;
for (c = 0; c < chunk; c++) {
int sysrq;
uport->icount.rx++;
if (port->brk && buf[c] == 0) {
port->brk = false;
if (uart_handle_break(uport))
continue;
}
sysrq = uart_prepare_sysrq_char(uport, buf[c]);
if (!sysrq)
tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
}
}
if (!drop)
tty_flip_buffer_push(tport);
}
#else
static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
{
}
#endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
static void handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
struct tty_port *tport = &uport->state->port;
int ret;
ret = tty_insert_flip_string(tport, port->rx_buf, bytes);
if (ret != bytes) {
dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n",
__func__, ret, bytes);
WARN_ON_ONCE(1);
}
uport->icount.rx += ret;
tty_flip_buffer_push(tport);
}
static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport)
{
return !readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
}
static void qcom_geni_serial_stop_tx_dma(struct uart_port *uport)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
bool done;
u32 m_irq_en;
if (!qcom_geni_serial_main_active(uport))
return;
if (port->tx_dma_addr) {
geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr,
port->tx_remaining);
port->tx_dma_addr = 0;
port->tx_remaining = 0;
}
m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
writel(m_irq_en, uport->membase + SE_GENI_M_IRQ_EN);
geni_se_cancel_m_cmd(&port->se);
done = qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
S_CMD_CANCEL_EN, true);
if (!done) {
geni_se_abort_m_cmd(&port->se);
done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_ABORT_EN, true);
if (!done)
dev_err_ratelimited(uport->dev, "M_CMD_ABORT_EN not set");
writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
}
writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
}
static void qcom_geni_serial_start_tx_dma(struct uart_port *uport)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
struct circ_buf *xmit = &uport->state->xmit;
unsigned int xmit_size;
int ret;
if (port->tx_dma_addr)
return;
if (uart_circ_empty(xmit))
return;
xmit_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
qcom_geni_serial_setup_tx(uport, xmit_size);
ret = geni_se_tx_dma_prep(&port->se, &xmit->buf[xmit->tail],
xmit_size, &port->tx_dma_addr);
if (ret) {
dev_err(uport->dev, "unable to start TX SE DMA: %d\n", ret);
qcom_geni_serial_stop_tx_dma(uport);
return;
}
port->tx_remaining = xmit_size;
}
static void qcom_geni_serial_start_tx_fifo(struct uart_port *uport)
{
u32 irq_en;
if (qcom_geni_serial_main_active(uport) ||
!qcom_geni_serial_tx_empty(uport))
return;
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
}
static void qcom_geni_serial_stop_tx_fifo(struct uart_port *uport)
{
u32 irq_en;
struct qcom_geni_serial_port *port = to_dev_port(uport);
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
writel(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
/* Possible stop tx is called multiple times. */
if (!qcom_geni_serial_main_active(uport))
return;
geni_se_cancel_m_cmd(&port->se);
if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_CANCEL_EN, true)) {
geni_se_abort_m_cmd(&port->se);
qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
M_CMD_ABORT_EN, true);
writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
}
writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
}
static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop)
{
u32 status;
u32 word_cnt;
u32 last_word_byte_cnt;
u32 last_word_partial;
u32 total_bytes;
status = readl(uport->membase + SE_GENI_RX_FIFO_STATUS);
word_cnt = status & RX_FIFO_WC_MSK;
last_word_partial = status & RX_LAST;
last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
RX_LAST_BYTE_VALID_SHFT;
if (!word_cnt)
return;
total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
if (last_word_partial && last_word_byte_cnt)
total_bytes += last_word_byte_cnt;
else
total_bytes += BYTES_PER_FIFO_WORD;
handle_rx_console(uport, total_bytes, drop);
}
static void qcom_geni_serial_stop_rx_fifo(struct uart_port *uport)
{
u32 irq_en;
struct qcom_geni_serial_port *port = to_dev_port(uport);
u32 s_irq_status;
irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
if (!qcom_geni_serial_secondary_active(uport))
return;
geni_se_cancel_s_cmd(&port->se);
qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
S_CMD_CANCEL_EN, true);
/*
* If timeout occurs secondary engine remains active
* and Abort sequence is executed.
*/
s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
/* Flush the Rx buffer */
if (s_irq_status & S_RX_FIFO_LAST_EN)
qcom_geni_serial_handle_rx_fifo(uport, true);
writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
if (qcom_geni_serial_secondary_active(uport))
qcom_geni_serial_abort_rx(uport);
}
static void qcom_geni_serial_start_rx_fifo(struct uart_port *uport)
{
u32 irq_en;
struct qcom_geni_serial_port *port = to_dev_port(uport);
if (qcom_geni_serial_secondary_active(uport))
qcom_geni_serial_stop_rx_fifo(uport);
geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
}
static void qcom_geni_serial_stop_rx_dma(struct uart_port *uport)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
if (!qcom_geni_serial_secondary_active(uport))
return;
geni_se_cancel_s_cmd(&port->se);
qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
S_CMD_CANCEL_EN, true);
if (qcom_geni_serial_secondary_active(uport))
qcom_geni_serial_abort_rx(uport);
if (port->rx_dma_addr) {
geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr,
DMA_RX_BUF_SIZE);
port->rx_dma_addr = 0;
}
}
static void qcom_geni_serial_start_rx_dma(struct uart_port *uport)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
int ret;
if (qcom_geni_serial_secondary_active(uport))
qcom_geni_serial_stop_rx_dma(uport);
geni_se_setup_s_cmd(&port->se, UART_START_READ, UART_PARAM_RFR_OPEN);
ret = geni_se_rx_dma_prep(&port->se, port->rx_buf,
DMA_RX_BUF_SIZE,
&port->rx_dma_addr);
if (ret) {
dev_err(uport->dev, "unable to start RX SE DMA: %d\n", ret);
qcom_geni_serial_stop_rx_dma(uport);
}
}
static void qcom_geni_serial_handle_rx_dma(struct uart_port *uport, bool drop)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
u32 rx_in;
int ret;
if (!qcom_geni_serial_secondary_active(uport))
return;
if (!port->rx_dma_addr)
return;
geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr, DMA_RX_BUF_SIZE);
port->rx_dma_addr = 0;
rx_in = readl(uport->membase + SE_DMA_RX_LEN_IN);
if (!rx_in) {
dev_warn(uport->dev, "serial engine reports 0 RX bytes in!\n");
return;
}
if (!drop)
handle_rx_uart(uport, rx_in, drop);
ret = geni_se_rx_dma_prep(&port->se, port->rx_buf,
DMA_RX_BUF_SIZE,
&port->rx_dma_addr);
if (ret) {
dev_err(uport->dev, "unable to start RX SE DMA: %d\n", ret);
qcom_geni_serial_stop_rx_dma(uport);
}
}
static void qcom_geni_serial_start_rx(struct uart_port *uport)
{
uport->ops->start_rx(uport);
}
static void qcom_geni_serial_stop_rx(struct uart_port *uport)
{
uport->ops->stop_rx(uport);
}
static void qcom_geni_serial_stop_tx(struct uart_port *uport)
{
uport->ops->stop_tx(uport);
}
static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
unsigned int remaining)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
struct circ_buf *xmit = &uport->state->xmit;
unsigned int tx_bytes;
u8 buf[BYTES_PER_FIFO_WORD];
while (remaining) {
memset(buf, 0, sizeof(buf));
tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
memcpy(buf, &xmit->buf[xmit->tail], tx_bytes);
uart_xmit_advance(uport, tx_bytes);
iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
remaining -= tx_bytes;
port->tx_remaining -= tx_bytes;
}
}
static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport,
bool done, bool active)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
struct circ_buf *xmit = &uport->state->xmit;
size_t avail;
size_t pending;
u32 status;
u32 irq_en;
unsigned int chunk;
status = readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
/* Complete the current tx command before taking newly added data */
if (active)
pending = port->tx_remaining;
else
pending = uart_circ_chars_pending(xmit);
/* All data has been transmitted and acknowledged as received */
if (!pending && !status && done) {
qcom_geni_serial_stop_tx_fifo(uport);
goto out_write_wakeup;
}
avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
avail *= BYTES_PER_FIFO_WORD;
chunk = min(avail, pending);
if (!chunk)
goto out_write_wakeup;
if (!port->tx_remaining) {
qcom_geni_serial_setup_tx(uport, pending);
port->tx_remaining = pending;
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
if (!(irq_en & M_TX_FIFO_WATERMARK_EN))
writel(irq_en | M_TX_FIFO_WATERMARK_EN,
uport->membase + SE_GENI_M_IRQ_EN);
}
qcom_geni_serial_send_chunk_fifo(uport, chunk);
/*
* The tx fifo watermark is level triggered and latched. Though we had
* cleared it in qcom_geni_serial_isr it will have already reasserted
* so we must clear it again here after our writes.
*/
writel(M_TX_FIFO_WATERMARK_EN,
uport->membase + SE_GENI_M_IRQ_CLEAR);
out_write_wakeup:
if (!port->tx_remaining) {
irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
if (irq_en & M_TX_FIFO_WATERMARK_EN)
writel(irq_en & ~M_TX_FIFO_WATERMARK_EN,
uport->membase + SE_GENI_M_IRQ_EN);
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(uport);
}
static void qcom_geni_serial_handle_tx_dma(struct uart_port *uport)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
struct circ_buf *xmit = &uport->state->xmit;
uart_xmit_advance(uport, port->tx_remaining);
geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr, port->tx_remaining);
port->tx_dma_addr = 0;
port->tx_remaining = 0;
if (!uart_circ_empty(xmit))
qcom_geni_serial_start_tx_dma(uport);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(uport);
}
static irqreturn_t qcom_geni_serial_isr(int isr, void *dev)
{
u32 m_irq_en;
u32 m_irq_status;
u32 s_irq_status;
u32 geni_status;
u32 dma;
u32 dma_tx_status;
u32 dma_rx_status;
struct uart_port *uport = dev;
bool drop_rx = false;
struct tty_port *tport = &uport->state->port;
struct qcom_geni_serial_port *port = to_dev_port(uport);
if (uport->suspended)
return IRQ_NONE;
spin_lock(&uport->lock);
m_irq_status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
dma_tx_status = readl(uport->membase + SE_DMA_TX_IRQ_STAT);
dma_rx_status = readl(uport->membase + SE_DMA_RX_IRQ_STAT);
geni_status = readl(uport->membase + SE_GENI_STATUS);
dma = readl(uport->membase + SE_GENI_DMA_MODE_EN);
m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
writel(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR);
writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
writel(dma_tx_status, uport->membase + SE_DMA_TX_IRQ_CLR);
writel(dma_rx_status, uport->membase + SE_DMA_RX_IRQ_CLR);
if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN))
goto out_unlock;
if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
uport->icount.overrun++;
tty_insert_flip_char(tport, 0, TTY_OVERRUN);
}
if (s_irq_status & (S_GP_IRQ_0_EN | S_GP_IRQ_1_EN)) {
if (s_irq_status & S_GP_IRQ_0_EN)
uport->icount.parity++;
drop_rx = true;
} else if (s_irq_status & (S_GP_IRQ_2_EN | S_GP_IRQ_3_EN)) {
uport->icount.brk++;
port->brk = true;
}
if (dma) {
if (dma_tx_status & TX_DMA_DONE)
qcom_geni_serial_handle_tx_dma(uport);
if (dma_rx_status) {
if (dma_rx_status & RX_RESET_DONE)
goto out_unlock;
if (dma_rx_status & RX_DMA_PARITY_ERR) {
uport->icount.parity++;
drop_rx = true;
}
if (dma_rx_status & RX_DMA_BREAK)
uport->icount.brk++;
if (dma_rx_status & (RX_DMA_DONE | RX_EOT))
qcom_geni_serial_handle_rx_dma(uport, drop_rx);
}
} else {
if (m_irq_status & m_irq_en &
(M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN))
qcom_geni_serial_handle_tx_fifo(uport,
m_irq_status & M_CMD_DONE_EN,
geni_status & M_GENI_CMD_ACTIVE);
if (s_irq_status & (S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN))
qcom_geni_serial_handle_rx_fifo(uport, drop_rx);
}
out_unlock:
uart_unlock_and_check_sysrq(uport);
return IRQ_HANDLED;
}
static int setup_fifos(struct qcom_geni_serial_port *port)
{
struct uart_port *uport;
u32 old_rx_fifo_depth = port->rx_fifo_depth;
uport = &port->uport;
port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se);
port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se);
port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se);
uport->fifosize =
(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
if (port->rx_buf && (old_rx_fifo_depth != port->rx_fifo_depth) && port->rx_fifo_depth) {
port->rx_buf = devm_krealloc(uport->dev, port->rx_buf,
port->rx_fifo_depth * sizeof(u32),
GFP_KERNEL);
if (!port->rx_buf)
return -ENOMEM;
}
return 0;
}
static void qcom_geni_serial_shutdown(struct uart_port *uport)
{
disable_irq(uport->irq);
if (uart_console(uport))
return;
qcom_geni_serial_stop_tx(uport);
qcom_geni_serial_stop_rx(uport);
}
static int qcom_geni_serial_port_setup(struct uart_port *uport)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
u32 rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT;
u32 proto;
u32 pin_swap;
int ret;
proto = geni_se_read_proto(&port->se);
if (proto != GENI_SE_UART) {
dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
return -ENXIO;
}
qcom_geni_serial_stop_rx(uport);
ret = setup_fifos(port);
if (ret)
return ret;
writel(rxstale, uport->membase + SE_UART_RX_STALE_CNT);
pin_swap = readl(uport->membase + SE_UART_IO_MACRO_CTRL);
if (port->rx_tx_swap) {
pin_swap &= ~DEFAULT_IO_MACRO_IO2_IO3_MASK;
pin_swap |= IO_MACRO_IO2_IO3_SWAP;
}
if (port->cts_rts_swap) {
pin_swap &= ~DEFAULT_IO_MACRO_IO0_IO1_MASK;
pin_swap |= IO_MACRO_IO0_SEL;
}
/* Configure this register if RX-TX, CTS-RTS pins are swapped */
if (port->rx_tx_swap || port->cts_rts_swap)
writel(pin_swap, uport->membase + SE_UART_IO_MACRO_CTRL);
/*
* Make an unconditional cancel on the main sequencer to reset
* it else we could end up in data loss scenarios.
*/
if (uart_console(uport))
qcom_geni_serial_poll_tx_done(uport);
geni_se_config_packing(&port->se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
false, true, true);
geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);
geni_se_select_mode(&port->se, port->dev_data->mode);
qcom_geni_serial_start_rx(uport);
port->setup = true;
return 0;
}
static int qcom_geni_serial_startup(struct uart_port *uport)
{
int ret;
struct qcom_geni_serial_port *port = to_dev_port(uport);
if (!port->setup) {
ret = qcom_geni_serial_port_setup(uport);
if (ret)
return ret;
}
enable_irq(uport->irq);
return 0;
}
static unsigned long find_clk_rate_in_tol(struct clk *clk, unsigned int desired_clk,
unsigned int *clk_div, unsigned int percent_tol)
{
unsigned long freq;
unsigned long div, maxdiv;
u64 mult;
unsigned long offset, abs_tol, achieved;
abs_tol = div_u64((u64)desired_clk * percent_tol, 100);
maxdiv = CLK_DIV_MSK >> CLK_DIV_SHFT;
div = 1;
while (div <= maxdiv) {
mult = (u64)div * desired_clk;
if (mult != (unsigned long)mult)
break;
offset = div * abs_tol;
freq = clk_round_rate(clk, mult - offset);
/* Can only get lower if we're done */
if (freq < mult - offset)
break;
/*
* Re-calculate div in case rounding skipped rates but we
* ended up at a good one, then check for a match.
*/
div = DIV_ROUND_CLOSEST(freq, desired_clk);
achieved = DIV_ROUND_CLOSEST(freq, div);
if (achieved <= desired_clk + abs_tol &&
achieved >= desired_clk - abs_tol) {
*clk_div = div;
return freq;
}
div = DIV_ROUND_UP(freq, desired_clk);
}
return 0;
}
static unsigned long get_clk_div_rate(struct clk *clk, unsigned int baud,
unsigned int sampling_rate, unsigned int *clk_div)
{
unsigned long ser_clk;
unsigned long desired_clk;
desired_clk = baud * sampling_rate;
if (!desired_clk)
return 0;
/*
* try to find a clock rate within 2% tolerance, then within 5%
*/
ser_clk = find_clk_rate_in_tol(clk, desired_clk, clk_div, 2);
if (!ser_clk)
ser_clk = find_clk_rate_in_tol(clk, desired_clk, clk_div, 5);
return ser_clk;
}
static void qcom_geni_serial_set_termios(struct uart_port *uport,
struct ktermios *termios,
const struct ktermios *old)
{
unsigned int baud;
u32 bits_per_char;
u32 tx_trans_cfg;
u32 tx_parity_cfg;
u32 rx_trans_cfg;
u32 rx_parity_cfg;
u32 stop_bit_len;
unsigned int clk_div;
u32 ser_clk_cfg;
struct qcom_geni_serial_port *port = to_dev_port(uport);
unsigned long clk_rate;
u32 ver, sampling_rate;
unsigned int avg_bw_core;
qcom_geni_serial_stop_rx(uport);
/* baud rate */
baud = uart_get_baud_rate(uport, termios, old, 300, 4000000);
port->baud = baud;
sampling_rate = UART_OVERSAMPLING;
/* Sampling rate is halved for IP versions >= 2.5 */
ver = geni_se_get_qup_hw_version(&port->se);
if (ver >= QUP_SE_VERSION_2_5)
sampling_rate /= 2;
clk_rate = get_clk_div_rate(port->se.clk, baud,
sampling_rate, &clk_div);
if (!clk_rate) {
dev_err(port->se.dev,
"Couldn't find suitable clock rate for %u\n",
baud * sampling_rate);
goto out_restart_rx;
}
dev_dbg(port->se.dev, "desired_rate-%u, clk_rate-%lu, clk_div-%u\n",
baud * sampling_rate, clk_rate, clk_div);
uport->uartclk = clk_rate;
dev_pm_opp_set_rate(uport->dev, clk_rate);
ser_clk_cfg = SER_CLK_EN;
ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
/*
* Bump up BW vote on CPU and CORE path as driver supports FIFO mode
* only.
*/
avg_bw_core = (baud > 115200) ? Bps_to_icc(CORE_2X_50_MHZ)
: GENI_DEFAULT_BW;
port->se.icc_paths[GENI_TO_CORE].avg_bw = avg_bw_core;
port->se.icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(baud);
geni_icc_set_bw(&port->se);
/* parity */
tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG);
tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG);
rx_trans_cfg = readl(uport->membase + SE_UART_RX_TRANS_CFG);
rx_parity_cfg = readl(uport->membase + SE_UART_RX_PARITY_CFG);
if (termios->c_cflag & PARENB) {
tx_trans_cfg |= UART_TX_PAR_EN;
rx_trans_cfg |= UART_RX_PAR_EN;
tx_parity_cfg |= PAR_CALC_EN;
rx_parity_cfg |= PAR_CALC_EN;
if (termios->c_cflag & PARODD) {
tx_parity_cfg |= PAR_ODD;
rx_parity_cfg |= PAR_ODD;
} else if (termios->c_cflag & CMSPAR) {
tx_parity_cfg |= PAR_SPACE;
rx_parity_cfg |= PAR_SPACE;
} else {
tx_parity_cfg |= PAR_EVEN;
rx_parity_cfg |= PAR_EVEN;
}
} else {
tx_trans_cfg &= ~UART_TX_PAR_EN;
rx_trans_cfg &= ~UART_RX_PAR_EN;
tx_parity_cfg &= ~PAR_CALC_EN;
rx_parity_cfg &= ~PAR_CALC_EN;
}
/* bits per char */
bits_per_char = tty_get_char_size(termios->c_cflag);
/* stop bits */
if (termios->c_cflag & CSTOPB)
stop_bit_len = TX_STOP_BIT_LEN_2;
else
stop_bit_len = TX_STOP_BIT_LEN_1;
/* flow control, clear the CTS_MASK bit if using flow control. */
if (termios->c_cflag & CRTSCTS)
tx_trans_cfg &= ~UART_CTS_MASK;
else
tx_trans_cfg |= UART_CTS_MASK;
if (baud)
uart_update_timeout(uport, termios->c_cflag, baud);
if (!uart_console(uport))
writel(port->loopback,
uport->membase + SE_UART_LOOPBACK_CFG);
writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
writel(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG);
writel(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG);
out_restart_rx:
qcom_geni_serial_start_rx(uport);
}
#ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
static int qcom_geni_console_setup(struct console *co, char *options)
{
struct uart_port *uport;
struct qcom_geni_serial_port *port;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
int ret;
if (co->index >= GENI_UART_CONS_PORTS || co->index < 0)
return -ENXIO;
port = get_port_from_line(co->index, true);
if (IS_ERR(port)) {
pr_err("Invalid line %d\n", co->index);
return PTR_ERR(port);
}
uport = &port->uport;
if (unlikely(!uport->membase))
return -ENXIO;
if (!port->setup) {
ret = qcom_geni_serial_port_setup(uport);
if (ret)
return ret;
}
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(uport, co, baud, parity, bits, flow);
}
static void qcom_geni_serial_earlycon_write(struct console *con,
const char *s, unsigned int n)
{
struct earlycon_device *dev = con->data;
__qcom_geni_serial_console_write(&dev->port, s, n);
}
#ifdef CONFIG_CONSOLE_POLL
static int qcom_geni_serial_earlycon_read(struct console *con,
char *s, unsigned int n)
{
struct earlycon_device *dev = con->data;
struct uart_port *uport = &dev->port;
int num_read = 0;
int ch;
while (num_read < n) {
ch = qcom_geni_serial_get_char(uport);
if (ch == NO_POLL_CHAR)
break;
s[num_read++] = ch;
}
return num_read;
}
static void __init qcom_geni_serial_enable_early_read(struct geni_se *se,
struct console *con)
{
geni_se_setup_s_cmd(se, UART_START_READ, 0);
con->read = qcom_geni_serial_earlycon_read;
}
#else
static inline void qcom_geni_serial_enable_early_read(struct geni_se *se,
struct console *con) { }
#endif
static struct qcom_geni_private_data earlycon_private_data;
static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
const char *opt)
{
struct uart_port *uport = &dev->port;
u32 tx_trans_cfg;
u32 tx_parity_cfg = 0; /* Disable Tx Parity */
u32 rx_trans_cfg = 0;
u32 rx_parity_cfg = 0; /* Disable Rx Parity */
u32 stop_bit_len = 0; /* Default stop bit length - 1 bit */
u32 bits_per_char;
struct geni_se se;
if (!uport->membase)
return -EINVAL;
uport->private_data = &earlycon_private_data;
memset(&se, 0, sizeof(se));
se.base = uport->membase;
if (geni_se_read_proto(&se) != GENI_SE_UART)
return -ENXIO;
/*
* Ignore Flow control.
* n = 8.
*/
tx_trans_cfg = UART_CTS_MASK;
bits_per_char = BITS_PER_BYTE;
/*
* Make an unconditional cancel on the main sequencer to reset
* it else we could end up in data loss scenarios.
*/
qcom_geni_serial_poll_tx_done(uport);
qcom_geni_serial_abort_rx(uport);
geni_se_config_packing(&se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
false, true, true);
geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
geni_se_select_mode(&se, GENI_SE_FIFO);
writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
dev->con->write = qcom_geni_serial_earlycon_write;
dev->con->setup = NULL;
qcom_geni_serial_enable_early_read(&se, dev->con);
return 0;
}
OF_EARLYCON_DECLARE(qcom_geni, "qcom,geni-debug-uart",
qcom_geni_serial_earlycon_setup);
static int __init console_register(struct uart_driver *drv)
{
return uart_register_driver(drv);
}
static void console_unregister(struct uart_driver *drv)
{
uart_unregister_driver(drv);
}
static struct console cons_ops = {
.name = "ttyMSM",
.write = qcom_geni_serial_console_write,
.device = uart_console_device,
.setup = qcom_geni_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &qcom_geni_console_driver,
};
static struct uart_driver qcom_geni_console_driver = {
.owner = THIS_MODULE,
.driver_name = "qcom_geni_console",
.dev_name = "ttyMSM",
.nr = GENI_UART_CONS_PORTS,
.cons = &cons_ops,
};
#else
static int console_register(struct uart_driver *drv)
{
return 0;
}
static void console_unregister(struct uart_driver *drv)
{
}
#endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
static struct uart_driver qcom_geni_uart_driver = {
.owner = THIS_MODULE,
.driver_name = "qcom_geni_uart",
.dev_name = "ttyHS",
.nr = GENI_UART_PORTS,
};
static void qcom_geni_serial_pm(struct uart_port *uport,
unsigned int new_state, unsigned int old_state)
{
struct qcom_geni_serial_port *port = to_dev_port(uport);
/* If we've never been called, treat it as off */
if (old_state == UART_PM_STATE_UNDEFINED)
old_state = UART_PM_STATE_OFF;
if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) {
geni_icc_enable(&port->se);
geni_se_resources_on(&port->se);
} else if (new_state == UART_PM_STATE_OFF &&
old_state == UART_PM_STATE_ON) {
geni_se_resources_off(&port->se);
geni_icc_disable(&port->se);
}
}
static const struct uart_ops qcom_geni_console_pops = {
.tx_empty = qcom_geni_serial_tx_empty,
.stop_tx = qcom_geni_serial_stop_tx_fifo,
.start_tx = qcom_geni_serial_start_tx_fifo,
.stop_rx = qcom_geni_serial_stop_rx_fifo,
.start_rx = qcom_geni_serial_start_rx_fifo,
.set_termios = qcom_geni_serial_set_termios,
.startup = qcom_geni_serial_startup,
.request_port = qcom_geni_serial_request_port,
.config_port = qcom_geni_serial_config_port,
.shutdown = qcom_geni_serial_shutdown,
.type = qcom_geni_serial_get_type,
.set_mctrl = qcom_geni_serial_set_mctrl,
.get_mctrl = qcom_geni_serial_get_mctrl,
#ifdef CONFIG_CONSOLE_POLL
.poll_get_char = qcom_geni_serial_get_char,
.poll_put_char = qcom_geni_serial_poll_put_char,
.poll_init = qcom_geni_serial_port_setup,
#endif
.pm = qcom_geni_serial_pm,
};
static const struct uart_ops qcom_geni_uart_pops = {
.tx_empty = qcom_geni_serial_tx_empty,
.stop_tx = qcom_geni_serial_stop_tx_dma,
.start_tx = qcom_geni_serial_start_tx_dma,
.start_rx = qcom_geni_serial_start_rx_dma,
.stop_rx = qcom_geni_serial_stop_rx_dma,
.set_termios = qcom_geni_serial_set_termios,
.startup = qcom_geni_serial_startup,
.request_port = qcom_geni_serial_request_port,
.config_port = qcom_geni_serial_config_port,
.shutdown = qcom_geni_serial_shutdown,
.type = qcom_geni_serial_get_type,
.set_mctrl = qcom_geni_serial_set_mctrl,
.get_mctrl = qcom_geni_serial_get_mctrl,
.pm = qcom_geni_serial_pm,
};
static int qcom_geni_serial_probe(struct platform_device *pdev)
{
int ret = 0;
int line;
struct qcom_geni_serial_port *port;
struct uart_port *uport;
struct resource *res;
int irq;
struct uart_driver *drv;
const struct qcom_geni_device_data *data;
data = of_device_get_match_data(&pdev->dev);
if (!data)
return -EINVAL;
if (data->console) {
drv = &qcom_geni_console_driver;
line = of_alias_get_id(pdev->dev.of_node, "serial");
} else {
drv = &qcom_geni_uart_driver;
line = of_alias_get_id(pdev->dev.of_node, "serial");
if (line == -ENODEV) /* compat with non-standard aliases */
line = of_alias_get_id(pdev->dev.of_node, "hsuart");
}
port = get_port_from_line(line, data->console);
if (IS_ERR(port)) {
dev_err(&pdev->dev, "Invalid line %d\n", line);
return PTR_ERR(port);
}
uport = &port->uport;
/* Don't allow 2 drivers to access the same port */
if (uport->private_data)
return -ENODEV;
uport->dev = &pdev->dev;
port->dev_data = data;
port->se.dev = &pdev->dev;
port->se.wrapper = dev_get_drvdata(pdev->dev.parent);
port->se.clk = devm_clk_get(&pdev->dev, "se");
if (IS_ERR(port->se.clk)) {
ret = PTR_ERR(port->se.clk);
dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
return ret;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
uport->mapbase = res->start;
port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
if (!data->console) {
port->rx_buf = devm_kzalloc(uport->dev,
DMA_RX_BUF_SIZE, GFP_KERNEL);
if (!port->rx_buf)
return -ENOMEM;
}
ret = geni_icc_get(&port->se, NULL);
if (ret)
return ret;
port->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW;
port->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
/* Set BW for register access */
ret = geni_icc_set_bw(&port->se);
if (ret)
return ret;
port->name = devm_kasprintf(uport->dev, GFP_KERNEL,
"qcom_geni_serial_%s%d",
uart_console(uport) ? "console" : "uart", uport->line);
if (!port->name)
return -ENOMEM;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
uport->irq = irq;
uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_QCOM_GENI_CONSOLE);
if (!data->console)
port->wakeup_irq = platform_get_irq_optional(pdev, 1);
if (of_property_read_bool(pdev->dev.of_node, "rx-tx-swap"))
port->rx_tx_swap = true;
if (of_property_read_bool(pdev->dev.of_node, "cts-rts-swap"))
port->cts_rts_swap = true;
ret = devm_pm_opp_set_clkname(&pdev->dev, "se");
if (ret)
return ret;
/* OPP table is optional */
ret = devm_pm_opp_of_add_table(&pdev->dev);
if (ret && ret != -ENODEV) {
dev_err(&pdev->dev, "invalid OPP table in device tree\n");
return ret;
}
port->private_data.drv = drv;
uport->private_data = &port->private_data;
platform_set_drvdata(pdev, port);
irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
IRQF_TRIGGER_HIGH, port->name, uport);
if (ret) {
dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
return ret;
}
ret = uart_add_one_port(drv, uport);
if (ret)
return ret;
/*
* Set pm_runtime status as ACTIVE so that wakeup_irq gets
* enabled/disabled from dev_pm_arm_wake_irq during system
* suspend/resume respectively.
*/
pm_runtime_set_active(&pdev->dev);
if (port->wakeup_irq > 0) {
device_init_wakeup(&pdev->dev, true);
ret = dev_pm_set_dedicated_wake_irq(&pdev->dev,
port->wakeup_irq);
if (ret) {
device_init_wakeup(&pdev->dev, false);
uart_remove_one_port(drv, uport);
return ret;
}
}
return 0;
}
static int qcom_geni_serial_remove(struct platform_device *pdev)
{
struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
struct uart_driver *drv = port->private_data.drv;
dev_pm_clear_wake_irq(&pdev->dev);
device_init_wakeup(&pdev->dev, false);
uart_remove_one_port(drv, &port->uport);
return 0;
}
static int qcom_geni_serial_sys_suspend(struct device *dev)
{
struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
struct uart_port *uport = &port->uport;
struct qcom_geni_private_data *private_data = uport->private_data;
/*
* This is done so we can hit the lowest possible state in suspend
* even with no_console_suspend
*/
if (uart_console(uport)) {
geni_icc_set_tag(&port->se, QCOM_ICC_TAG_ACTIVE_ONLY);
geni_icc_set_bw(&port->se);
}
return uart_suspend_port(private_data->drv, uport);
}
static int qcom_geni_serial_sys_resume(struct device *dev)
{
int ret;
struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
struct uart_port *uport = &port->uport;
struct qcom_geni_private_data *private_data = uport->private_data;
ret = uart_resume_port(private_data->drv, uport);
if (uart_console(uport)) {
geni_icc_set_tag(&port->se, QCOM_ICC_TAG_ALWAYS);
geni_icc_set_bw(&port->se);
}
return ret;
}
static int qcom_geni_serial_sys_hib_resume(struct device *dev)
{
int ret = 0;
struct uart_port *uport;
struct qcom_geni_private_data *private_data;
struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
uport = &port->uport;
private_data = uport->private_data;
if (uart_console(uport)) {
geni_icc_set_tag(&port->se, 0x7);
geni_icc_set_bw(&port->se);
ret = uart_resume_port(private_data->drv, uport);
/*
* For hibernation usecase clients for
* console UART won't call port setup during restore,
* hence call port setup for console uart.
*/
qcom_geni_serial_port_setup(uport);
} else {
/*
* Peripheral register settings are lost during hibernation.
* Update setup flag such that port setup happens again
* during next session. Clients of HS-UART will close and
* open the port during hibernation.
*/
port->setup = false;
}
return ret;
}
static const struct qcom_geni_device_data qcom_geni_console_data = {
.console = true,
.mode = GENI_SE_FIFO,
};
static const struct qcom_geni_device_data qcom_geni_uart_data = {
.console = false,
.mode = GENI_SE_DMA,
};
static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
.suspend = pm_sleep_ptr(qcom_geni_serial_sys_suspend),
.resume = pm_sleep_ptr(qcom_geni_serial_sys_resume),
.freeze = pm_sleep_ptr(qcom_geni_serial_sys_suspend),
.poweroff = pm_sleep_ptr(qcom_geni_serial_sys_suspend),
.restore = pm_sleep_ptr(qcom_geni_serial_sys_hib_resume),
.thaw = pm_sleep_ptr(qcom_geni_serial_sys_hib_resume),
};
static const struct of_device_id qcom_geni_serial_match_table[] = {
{
.compatible = "qcom,geni-debug-uart",
.data = &qcom_geni_console_data,
},
{
.compatible = "qcom,geni-uart",
.data = &qcom_geni_uart_data,
},
{}
};
MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);
static struct platform_driver qcom_geni_serial_platform_driver = {
.remove = qcom_geni_serial_remove,
.probe = qcom_geni_serial_probe,
.driver = {
.name = "qcom_geni_serial",
.of_match_table = qcom_geni_serial_match_table,
.pm = &qcom_geni_serial_pm_ops,
},
};
static int __init qcom_geni_serial_init(void)
{
int ret;
ret = console_register(&qcom_geni_console_driver);
if (ret)
return ret;
ret = uart_register_driver(&qcom_geni_uart_driver);
if (ret) {
console_unregister(&qcom_geni_console_driver);
return ret;
}
ret = platform_driver_register(&qcom_geni_serial_platform_driver);
if (ret) {
console_unregister(&qcom_geni_console_driver);
uart_unregister_driver(&qcom_geni_uart_driver);
}
return ret;
}
module_init(qcom_geni_serial_init);
static void __exit qcom_geni_serial_exit(void)
{
platform_driver_unregister(&qcom_geni_serial_platform_driver);
console_unregister(&qcom_geni_console_driver);
uart_unregister_driver(&qcom_geni_uart_driver);
}
module_exit(qcom_geni_serial_exit);
MODULE_DESCRIPTION("Serial driver for GENI based QUP cores");
MODULE_LICENSE("GPL v2");