| /* |
| * 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) |
| 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 done; |
| } |
| |
| 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: |
| if (np) |
| of_node_put(np); |
| 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 */ |
| |