arch/powerpc/platforms/embedded6xx/usbgecko_udbg.c - linux - Git at Google

 /*
  * 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.
  */
 static 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 */
	/*
	* 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.
	*/
	static 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 */