mirror of
https://github.com/torvalds/linux.git
synced 2024-12-28 22:02:28 +00:00
6609ed14de
Simplify the error path to avoid calling of_node_put when it is not needed. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
329 lines
6.7 KiB
C
329 lines
6.7 KiB
C
/*
|
|
* arch/powerpc/platforms/embedded6xx/usbgecko_udbg.c
|
|
*
|
|
* udbg serial input/output routines for the USB Gecko adapter.
|
|
* Copyright (C) 2008-2009 The GameCube Linux Team
|
|
* Copyright (C) 2008,2009 Albert Herranz
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
*/
|
|
|
|
#include <mm/mmu_decl.h>
|
|
|
|
#include <asm/io.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/udbg.h>
|
|
#include <asm/fixmap.h>
|
|
|
|
#include "usbgecko_udbg.h"
|
|
|
|
|
|
#define EXI_CLK_32MHZ 5
|
|
|
|
#define EXI_CSR 0x00
|
|
#define EXI_CSR_CLKMASK (0x7<<4)
|
|
#define EXI_CSR_CLK_32MHZ (EXI_CLK_32MHZ<<4)
|
|
#define EXI_CSR_CSMASK (0x7<<7)
|
|
#define EXI_CSR_CS_0 (0x1<<7) /* Chip Select 001 */
|
|
|
|
#define EXI_CR 0x0c
|
|
#define EXI_CR_TSTART (1<<0)
|
|
#define EXI_CR_WRITE (1<<2)
|
|
#define EXI_CR_READ_WRITE (2<<2)
|
|
#define EXI_CR_TLEN(len) (((len)-1)<<4)
|
|
|
|
#define EXI_DATA 0x10
|
|
|
|
#define UG_READ_ATTEMPTS 100
|
|
#define UG_WRITE_ATTEMPTS 100
|
|
|
|
|
|
static void __iomem *ug_io_base;
|
|
|
|
/*
|
|
* Performs one input/output transaction between the exi host and the usbgecko.
|
|
*/
|
|
static u32 ug_io_transaction(u32 in)
|
|
{
|
|
u32 __iomem *csr_reg = ug_io_base + EXI_CSR;
|
|
u32 __iomem *data_reg = ug_io_base + EXI_DATA;
|
|
u32 __iomem *cr_reg = ug_io_base + EXI_CR;
|
|
u32 csr, data, cr;
|
|
|
|
/* select */
|
|
csr = EXI_CSR_CLK_32MHZ | EXI_CSR_CS_0;
|
|
out_be32(csr_reg, csr);
|
|
|
|
/* read/write */
|
|
data = in;
|
|
out_be32(data_reg, data);
|
|
cr = EXI_CR_TLEN(2) | EXI_CR_READ_WRITE | EXI_CR_TSTART;
|
|
out_be32(cr_reg, cr);
|
|
|
|
while (in_be32(cr_reg) & EXI_CR_TSTART)
|
|
barrier();
|
|
|
|
/* deselect */
|
|
out_be32(csr_reg, 0);
|
|
|
|
/* result */
|
|
data = in_be32(data_reg);
|
|
|
|
return data;
|
|
}
|
|
|
|
/*
|
|
* Returns true if an usbgecko adapter is found.
|
|
*/
|
|
static int ug_is_adapter_present(void)
|
|
{
|
|
if (!ug_io_base)
|
|
return 0;
|
|
|
|
return ug_io_transaction(0x90000000) == 0x04700000;
|
|
}
|
|
|
|
/*
|
|
* Returns true if the TX fifo is ready for transmission.
|
|
*/
|
|
static int ug_is_txfifo_ready(void)
|
|
{
|
|
return ug_io_transaction(0xc0000000) & 0x04000000;
|
|
}
|
|
|
|
/*
|
|
* Tries to transmit a character.
|
|
* If the TX fifo is not ready the result is undefined.
|
|
*/
|
|
static void ug_raw_putc(char ch)
|
|
{
|
|
ug_io_transaction(0xb0000000 | (ch << 20));
|
|
}
|
|
|
|
/*
|
|
* Transmits a character.
|
|
* It silently fails if the TX fifo is not ready after a number of retries.
|
|
*/
|
|
static void ug_putc(char ch)
|
|
{
|
|
int count = UG_WRITE_ATTEMPTS;
|
|
|
|
if (!ug_io_base)
|
|
return;
|
|
|
|
if (ch == '\n')
|
|
ug_putc('\r');
|
|
|
|
while (!ug_is_txfifo_ready() && count--)
|
|
barrier();
|
|
if (count >= 0)
|
|
ug_raw_putc(ch);
|
|
}
|
|
|
|
/*
|
|
* Returns true if the RX fifo is ready for transmission.
|
|
*/
|
|
static int ug_is_rxfifo_ready(void)
|
|
{
|
|
return ug_io_transaction(0xd0000000) & 0x04000000;
|
|
}
|
|
|
|
/*
|
|
* Tries to receive a character.
|
|
* If a character is unavailable the function returns -1.
|
|
*/
|
|
static int ug_raw_getc(void)
|
|
{
|
|
u32 data = ug_io_transaction(0xa0000000);
|
|
if (data & 0x08000000)
|
|
return (data >> 16) & 0xff;
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Receives a character.
|
|
* It fails if the RX fifo is not ready after a number of retries.
|
|
*/
|
|
static int ug_getc(void)
|
|
{
|
|
int count = UG_READ_ATTEMPTS;
|
|
|
|
if (!ug_io_base)
|
|
return -1;
|
|
|
|
while (!ug_is_rxfifo_ready() && count--)
|
|
barrier();
|
|
return ug_raw_getc();
|
|
}
|
|
|
|
/*
|
|
* udbg functions.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Transmits a character.
|
|
*/
|
|
void ug_udbg_putc(char ch)
|
|
{
|
|
ug_putc(ch);
|
|
}
|
|
|
|
/*
|
|
* Receives a character. Waits until a character is available.
|
|
*/
|
|
static int ug_udbg_getc(void)
|
|
{
|
|
int ch;
|
|
|
|
while ((ch = ug_getc()) == -1)
|
|
barrier();
|
|
return ch;
|
|
}
|
|
|
|
/*
|
|
* Receives a character. If a character is not available, returns -1.
|
|
*/
|
|
static int ug_udbg_getc_poll(void)
|
|
{
|
|
if (!ug_is_rxfifo_ready())
|
|
return -1;
|
|
return ug_getc();
|
|
}
|
|
|
|
/*
|
|
* Retrieves and prepares the virtual address needed to access the hardware.
|
|
*/
|
|
static void __iomem *ug_udbg_setup_exi_io_base(struct device_node *np)
|
|
{
|
|
void __iomem *exi_io_base = NULL;
|
|
phys_addr_t paddr;
|
|
const unsigned int *reg;
|
|
|
|
reg = of_get_property(np, "reg", NULL);
|
|
if (reg) {
|
|
paddr = of_translate_address(np, reg);
|
|
if (paddr)
|
|
exi_io_base = ioremap(paddr, reg[1]);
|
|
}
|
|
return exi_io_base;
|
|
}
|
|
|
|
/*
|
|
* Checks if a USB Gecko adapter is inserted in any memory card slot.
|
|
*/
|
|
static void __iomem *ug_udbg_probe(void __iomem *exi_io_base)
|
|
{
|
|
int i;
|
|
|
|
/* look for a usbgecko on memcard slots A and B */
|
|
for (i = 0; i < 2; i++) {
|
|
ug_io_base = exi_io_base + 0x14 * i;
|
|
if (ug_is_adapter_present())
|
|
break;
|
|
}
|
|
if (i == 2)
|
|
ug_io_base = NULL;
|
|
return ug_io_base;
|
|
|
|
}
|
|
|
|
/*
|
|
* USB Gecko udbg support initialization.
|
|
*/
|
|
void __init ug_udbg_init(void)
|
|
{
|
|
struct device_node *np;
|
|
void __iomem *exi_io_base;
|
|
|
|
if (ug_io_base)
|
|
udbg_printf("%s: early -> final\n", __func__);
|
|
|
|
np = of_find_compatible_node(NULL, NULL, "nintendo,flipper-exi");
|
|
if (!np) {
|
|
udbg_printf("%s: EXI node not found\n", __func__);
|
|
goto out;
|
|
}
|
|
|
|
exi_io_base = ug_udbg_setup_exi_io_base(np);
|
|
if (!exi_io_base) {
|
|
udbg_printf("%s: failed to setup EXI io base\n", __func__);
|
|
goto done;
|
|
}
|
|
|
|
if (!ug_udbg_probe(exi_io_base)) {
|
|
udbg_printf("usbgecko_udbg: not found\n");
|
|
iounmap(exi_io_base);
|
|
} else {
|
|
udbg_putc = ug_udbg_putc;
|
|
udbg_getc = ug_udbg_getc;
|
|
udbg_getc_poll = ug_udbg_getc_poll;
|
|
udbg_printf("usbgecko_udbg: ready\n");
|
|
}
|
|
|
|
done:
|
|
of_node_put(np);
|
|
out:
|
|
return;
|
|
}
|
|
|
|
#ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
|
|
|
|
static phys_addr_t __init ug_early_grab_io_addr(void)
|
|
{
|
|
#if defined(CONFIG_GAMECUBE)
|
|
return 0x0c000000;
|
|
#elif defined(CONFIG_WII)
|
|
return 0x0d000000;
|
|
#else
|
|
#error Invalid platform for USB Gecko based early debugging.
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* USB Gecko early debug support initialization for udbg.
|
|
*/
|
|
void __init udbg_init_usbgecko(void)
|
|
{
|
|
void __iomem *early_debug_area;
|
|
void __iomem *exi_io_base;
|
|
|
|
/*
|
|
* At this point we have a BAT already setup that enables I/O
|
|
* to the EXI hardware.
|
|
*
|
|
* The BAT uses a virtual address range reserved at the fixmap.
|
|
* This must match the virtual address configured in
|
|
* head_32.S:setup_usbgecko_bat().
|
|
*/
|
|
early_debug_area = (void __iomem *)__fix_to_virt(FIX_EARLY_DEBUG_BASE);
|
|
exi_io_base = early_debug_area + 0x00006800;
|
|
|
|
/* try to detect a USB Gecko */
|
|
if (!ug_udbg_probe(exi_io_base))
|
|
return;
|
|
|
|
/* we found a USB Gecko, load udbg hooks */
|
|
udbg_putc = ug_udbg_putc;
|
|
udbg_getc = ug_udbg_getc;
|
|
udbg_getc_poll = ug_udbg_getc_poll;
|
|
|
|
/*
|
|
* Prepare again the same BAT for MMU_init.
|
|
* This allows udbg I/O to continue working after the MMU is
|
|
* turned on for real.
|
|
* It is safe to continue using the same virtual address as it is
|
|
* a reserved fixmap area.
|
|
*/
|
|
setbat(1, (unsigned long)early_debug_area,
|
|
ug_early_grab_io_addr(), 128*1024, PAGE_KERNEL_NCG);
|
|
}
|
|
|
|
#endif /* CONFIG_PPC_EARLY_DEBUG_USBGECKO */
|
|
|