[deliverable/linux.git] / arch / powerpc / platforms / embedded6xx / usbgecko_udbg.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 */
Commit	Line	Data
a166df08 AH	1	/*
	2	* arch/powerpc/platforms/embedded6xx/usbgecko_udbg.c
	3	*
	4	* udbg serial input/output routines for the USB Gecko adapter.
	5	* Copyright (C) 2008-2009 The GameCube Linux Team
	6	* Copyright (C) 2008,2009 Albert Herranz
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version 2
	11	* of the License, or (at your option) any later version.
	12	*
	13	*/
	14
	15	#include <mm/mmu_decl.h>
	16
	17	#include <asm/io.h>
	18	#include <asm/prom.h>
	19	#include <asm/udbg.h>
d1d56f8c	20	#include <asm/fixmap.h>
a166df08 AH	21
	22	#include "usbgecko_udbg.h"
	23
	24
	25	#define EXI_CLK_32MHZ 5
	26
	27	#define EXI_CSR 0x00
	28	#define EXI_CSR_CLKMASK (0x7<<4)
	29	#define EXI_CSR_CLK_32MHZ (EXI_CLK_32MHZ<<4)
	30	#define EXI_CSR_CSMASK (0x7<<7)
	31	#define EXI_CSR_CS_0 (0x1<<7) /* Chip Select 001 */
	32
	33	#define EXI_CR 0x0c
	34	#define EXI_CR_TSTART (1<<0)
	35	#define EXI_CR_WRITE (1<<2)
	36	#define EXI_CR_READ_WRITE (2<<2)
	37	#define EXI_CR_TLEN(len) (((len)-1)<<4)
	38
	39	#define EXI_DATA 0x10
	40
	41	#define UG_READ_ATTEMPTS 100
	42	#define UG_WRITE_ATTEMPTS 100
	43
	44
	45	static void __iomem *ug_io_base;
	46
	47	/*
	48	* Performs one input/output transaction between the exi host and the usbgecko.
	49	*/
	50	static u32 ug_io_transaction(u32 in)
	51	{
	52	u32 __iomem *csr_reg = ug_io_base + EXI_CSR;
	53	u32 __iomem *data_reg = ug_io_base + EXI_DATA;
	54	u32 __iomem *cr_reg = ug_io_base + EXI_CR;
	55	u32 csr, data, cr;
	56
	57	/* select */
	58	csr = EXI_CSR_CLK_32MHZ \| EXI_CSR_CS_0;
	59	out_be32(csr_reg, csr);
	60
	61	/* read/write */
	62	data = in;
	63	out_be32(data_reg, data);
	64	cr = EXI_CR_TLEN(2) \| EXI_CR_READ_WRITE \| EXI_CR_TSTART;
	65	out_be32(cr_reg, cr);
	66
	67	while (in_be32(cr_reg) & EXI_CR_TSTART)
	68	barrier();
	69
	70	/* deselect */
	71	out_be32(csr_reg, 0);
	72
	73	/* result */
	74	data = in_be32(data_reg);
	75
	76	return data;
	77	}
	78
	79	/*
	80	* Returns true if an usbgecko adapter is found.
	81	*/
	82	static int ug_is_adapter_present(void)
	83	{
	84	if (!ug_io_base)
85	return 0;
86
87	return ug_io_transaction(0x90000000) == 0x04700000;
88	}
89
90	/*
91	* Returns true if the TX fifo is ready for transmission.
92	*/
93	static int ug_is_txfifo_ready(void)
94	{
95	return ug_io_transaction(0xc0000000) & 0x04000000;
96	}
97
98	/*
99	* Tries to transmit a character.
100	* If the TX fifo is not ready the result is undefined.
101	*/
102	static void ug_raw_putc(char ch)
103	{
104	ug_io_transaction(0xb0000000 \| (ch << 20));
105	}
106
107	/*
108	* Transmits a character.
109	* It silently fails if the TX fifo is not ready after a number of retries.
110	*/
111	static void ug_putc(char ch)
112	{
113	int count = UG_WRITE_ATTEMPTS;
114
115	if (!ug_io_base)
116	return;
117
118	if (ch == '\n')
119	ug_putc('\r');
120
121	while (!ug_is_txfifo_ready() && count--)
122	barrier();
698cd335	123	if (count >= 0)
a166df08 AH	124	ug_raw_putc(ch);
	125	}
	126
	127	/*
	128	* Returns true if the RX fifo is ready for transmission.
	129	*/
	130	static int ug_is_rxfifo_ready(void)
	131	{
	132	return ug_io_transaction(0xd0000000) & 0x04000000;
	133	}
	134
	135	/*
	136	* Tries to receive a character.
	137	* If a character is unavailable the function returns -1.
	138	*/
	139	static int ug_raw_getc(void)
	140	{
	141	u32 data = ug_io_transaction(0xa0000000);
	142	if (data & 0x08000000)
	143	return (data >> 16) & 0xff;
	144	else
	145	return -1;
	146	}
	147
	148	/*
	149	* Receives a character.
	150	* It fails if the RX fifo is not ready after a number of retries.
	151	*/
	152	static int ug_getc(void)
	153	{
	154	int count = UG_READ_ATTEMPTS;
	155
	156	if (!ug_io_base)
	157	return -1;
	158
	159	while (!ug_is_rxfifo_ready() && count--)
	160	barrier();
	161	return ug_raw_getc();
	162	}
	163
	164	/*
	165	* udbg functions.
	166	*
	167	*/
	168
	169	/*
	170	* Transmits a character.
	171	*/
	172	void ug_udbg_putc(char ch)
	173	{
	174	ug_putc(ch);
	175	}
	176
	177	/*
	178	* Receives a character. Waits until a character is available.
	179	*/
	180	static int ug_udbg_getc(void)
	181	{
	182	int ch;
	183
	184	while ((ch = ug_getc()) == -1)
	185	barrier();
	186	return ch;
	187	}
188
189	/*
190	* Receives a character. If a character is not available, returns -1.
191	*/
192	static int ug_udbg_getc_poll(void)
193	{
194	if (!ug_is_rxfifo_ready())
195	return -1;
196	return ug_getc();
197	}
198
199	/*
200	* Retrieves and prepares the virtual address needed to access the hardware.
201	*/
202	static void __iomem ug_udbg_setup_exi_io_base(struct device_node np)
203	{
204	void __iomem *exi_io_base = NULL;
205	phys_addr_t paddr;
206	const unsigned int *reg;
207
208	reg = of_get_property(np, "reg", NULL);
209	if (reg) {
210	paddr = of_translate_address(np, reg);
211	if (paddr)
212	exi_io_base = ioremap(paddr, reg[1]);
213	}
214	return exi_io_base;
215	}
216
217	/*
218	* Checks if a USB Gecko adapter is inserted in any memory card slot.
219	*/
220	static void __iomem ug_udbg_probe(void __iomem exi_io_base)
221	{
222	int i;
223
224	/* look for a usbgecko on memcard slots A and B */
225	for (i = 0; i < 2; i++) {
226	ug_io_base = exi_io_base + 0x14 * i;
227	if (ug_is_adapter_present())
228	break;
229	}
230	if (i == 2)
231	ug_io_base = NULL;
232	return ug_io_base;
233
234	}
235
236	/*
237	* USB Gecko udbg support initialization.
238	*/
239	void __init ug_udbg_init(void)
240	{
241	struct device_node *np;
242	void __iomem *exi_io_base;
243
244	if (ug_io_base)
245	udbg_printf("%s: early -> final\n", __func__);
246
247	np = of_find_compatible_node(NULL, NULL, "nintendo,flipper-exi");
248	if (!np) {
249	udbg_printf("%s: EXI node not found\n", __func__);
6609ed14	250	goto out;
a166df08 AH	251	}
	252
	253	exi_io_base = ug_udbg_setup_exi_io_base(np);
	254	if (!exi_io_base) {
	255	udbg_printf("%s: failed to setup EXI io base\n", __func__);
	256	goto done;
	257	}
	258
	259	if (!ug_udbg_probe(exi_io_base)) {
	260	udbg_printf("usbgecko_udbg: not found\n");
	261	iounmap(exi_io_base);
	262	} else {
	263	udbg_putc = ug_udbg_putc;
	264	udbg_getc = ug_udbg_getc;
	265	udbg_getc_poll = ug_udbg_getc_poll;
	266	udbg_printf("usbgecko_udbg: ready\n");
	267	}
	268
	269	done:
6609ed14 JL	270	of_node_put(np);
6609ed14 JL	271	out:
a166df08 AH	272	return;
a166df08 AH	273	}
d1d56f8c AH	274
	275	#ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
	276
	277	static phys_addr_t __init ug_early_grab_io_addr(void)
	278	{
	279	#if defined(CONFIG_GAMECUBE)
	280	return 0x0c000000;
	281	#elif defined(CONFIG_WII)
	282	return 0x0d000000;
	283	#else
	284	#error Invalid platform for USB Gecko based early debugging.
	285	#endif
	286	}
	287
	288	/*
	289	* USB Gecko early debug support initialization for udbg.
	290	*/
	291	void __init udbg_init_usbgecko(void)
	292	{
	293	void __iomem *early_debug_area;
	294	void __iomem *exi_io_base;
	295
	296	/*
	297	* At this point we have a BAT already setup that enables I/O
	298	* to the EXI hardware.
	299	*
	300	* The BAT uses a virtual address range reserved at the fixmap.
	301	* This must match the virtual address configured in
	302	* head_32.S:setup_usbgecko_bat().
	303	*/
	304	early_debug_area = (void __iomem *)__fix_to_virt(FIX_EARLY_DEBUG_BASE);
	305	exi_io_base = early_debug_area + 0x00006800;
	306
	307	/* try to detect a USB Gecko */
	308	if (!ug_udbg_probe(exi_io_base))
	309	return;
	310
	311	/* we found a USB Gecko, load udbg hooks */
	312	udbg_putc = ug_udbg_putc;
	313	udbg_getc = ug_udbg_getc;
	314	udbg_getc_poll = ug_udbg_getc_poll;
	315
	316	/*
	317	* Prepare again the same BAT for MMU_init.
	318	* This allows udbg I/O to continue working after the MMU is
	319	* turned on for real.
	320	* It is safe to continue using the same virtual address as it is
	321	* a reserved fixmap area.
	322	*/
	323	setbat(1, (unsigned long)early_debug_area,
	324	ug_early_grab_io_addr(), 128*1024, PAGE_KERNEL_NCG);
	325	}
	326
	327	#endif /* CONFIG_PPC_EARLY_DEBUG_USBGECKO */
	328