diff options
Diffstat (limited to 'arch/mips/ddb5xxx/common/prom.c')
| -rw-r--r-- | arch/mips/ddb5xxx/common/prom.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/mips/ddb5xxx/common/prom.c b/arch/mips/ddb5xxx/common/prom.c new file mode 100644 index 0000000..b8d1f74 --- /dev/null +++ b/arch/mips/ddb5xxx/common/prom.c @@ -0,0 +1,142 @@ +/* + * Copyright 2001 MontaVista Software Inc. + * Author: jsun@mvista.com or jsun@junsun.net + * + * 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 <linux/config.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/bootmem.h> + +#include <asm/addrspace.h> +#include <asm/bootinfo.h> +#include <asm/ddb5xxx/ddb5xxx.h> +#include <asm/debug.h> + +const char *get_system_type(void) +{ + switch (mips_machtype) { + case MACH_NEC_DDB5074: return "NEC DDB Vrc-5074"; + case MACH_NEC_DDB5476: return "NEC DDB Vrc-5476"; + case MACH_NEC_DDB5477: return "NEC DDB Vrc-5477"; + case MACH_NEC_ROCKHOPPER: return "NEC Rockhopper"; + case MACH_NEC_ROCKHOPPERII: return "NEC RockhopperII"; + default: return "Unknown NEC board"; + } +} + +#if defined(CONFIG_DDB5477) +void ddb5477_runtime_detection(void); +#endif + +/* [jsun@junsun.net] PMON passes arguments in C main() style */ +void __init prom_init(void) +{ + int argc = fw_arg0; + char **arg = (char**) fw_arg1; + int i; + + /* if user passes kernel args, ignore the default one */ + if (argc > 1) + arcs_cmdline[0] = '\0'; + + /* arg[0] is "g", the rest is boot parameters */ + for (i = 1; i < argc; i++) { + if (strlen(arcs_cmdline) + strlen(arg[i] + 1) + >= sizeof(arcs_cmdline)) + break; + strcat(arcs_cmdline, arg[i]); + strcat(arcs_cmdline, " "); + } + + mips_machgroup = MACH_GROUP_NEC_DDB; + +#if defined(CONFIG_DDB5074) + mips_machtype = MACH_NEC_DDB5074; + add_memory_region(0, DDB_SDRAM_SIZE, BOOT_MEM_RAM); +#elif defined(CONFIG_DDB5476) + mips_machtype = MACH_NEC_DDB5476; + add_memory_region(0, DDB_SDRAM_SIZE, BOOT_MEM_RAM); +#elif defined(CONFIG_DDB5477) + ddb5477_runtime_detection(); + add_memory_region(0, board_ram_size, BOOT_MEM_RAM); +#endif +} + +unsigned long __init prom_free_prom_memory(void) +{ + return 0; +} + +#if defined(CONFIG_DDB5477) + +#define DEFAULT_LCS1_BASE 0x19000000 +#define TESTVAL1 'K' +#define TESTVAL2 'S' + +int board_ram_size; +void ddb5477_runtime_detection(void) +{ + volatile char *test_offset; + char saved_test_byte; + + /* Determine if this is a DDB5477 board, or a BSB-VR0300 + base board. We can tell by checking for the location of + the NVRAM. It lives at the beginning of LCS1 on the DDB5477, + and the beginning of LCS1 on the BSB-VR0300 is flash memory. + The first 2K of the NVRAM are reserved, so don't we'll poke + around just after that. + */ + + /* We can only use the PCI bus to distinquish between + the Rockhopper and RockhopperII backplanes and this must + wait until ddb5477_board_init() in setup.c after the 5477 + is initialized. So, until then handle + both Rockhopper and RockhopperII backplanes as Rockhopper 1 + */ + + test_offset = (char *)KSEG1ADDR(DEFAULT_LCS1_BASE + 0x800); + saved_test_byte = *test_offset; + + *test_offset = TESTVAL1; + if (*test_offset != TESTVAL1) { + /* We couldn't set our test value, so it must not be NVRAM, + so it's a BSB_VR0300 */ + mips_machtype = MACH_NEC_ROCKHOPPER; + } else { + /* We may have gotten lucky, and the TESTVAL1 was already + stored at the test location, so we must check a second + test value */ + *test_offset = TESTVAL2; + if (*test_offset != TESTVAL2) { + /* OK, we couldn't set this value either, so it must + definately be a BSB_VR0300 */ + mips_machtype = MACH_NEC_ROCKHOPPER; + } else { + /* We could change the value twice, so it must be + NVRAM, so it's a DDB_VRC5477 */ + mips_machtype = MACH_NEC_DDB5477; + } + } + /* Restore the original byte */ + *test_offset = saved_test_byte; + + /* before we know a better way, we will trust PMON for getting + * RAM size + */ + board_ram_size = 1 << (36 - (ddb_in32(DDB_SDRAM0) & 0xf)); + + db_run(printk("DDB run-time detection : %s, %d MB RAM\n", + mips_machtype == MACH_NEC_DDB5477 ? + "DDB5477" : "Rockhopper", + board_ram_size >> 20)); + + /* we can't handle ram size > 128 MB */ + db_assert(board_ram_size <= (128 << 20)); +} +#endif |
