diff options
Diffstat (limited to 'arch/powerpc/kernel/prom_init.c')
| -rw-r--r-- | arch/powerpc/kernel/prom_init.c | 110 |
1 files changed, 108 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c index bf3966d12565..1c1b44ec7642 100644 --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -168,6 +168,14 @@ static unsigned long __initdata prom_tce_alloc_start; static unsigned long __initdata prom_tce_alloc_end; #endif +static bool __initdata prom_radix_disable; + +struct platform_support { + bool hash_mmu; + bool radix_mmu; + bool radix_gtse; +}; + /* Platforms codes are now obsolete in the kernel. Now only used within this * file and ultimately gone too. Feel free to change them if you need, they * are not shared with anything outside of this file anymore @@ -626,6 +634,12 @@ static void __init early_cmdline_parse(void) prom_memory_limit = ALIGN(prom_memory_limit, 0x1000000); #endif } + + opt = strstr(prom_cmd_line, "disable_radix"); + if (opt) { + prom_debug("Radix disabled from cmdline\n"); + prom_radix_disable = true; + } } #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV) @@ -695,6 +709,8 @@ struct option_vector5 { u8 byte22; u8 intarch; u8 mmu; + u8 hash_ext; + u8 radix_ext; } __packed; struct option_vector6 { @@ -850,8 +866,9 @@ struct ibm_arch_vec __cacheline_aligned ibm_architecture_vec = { .reserved3 = 0, .subprocessors = 1, .intarch = 0, - .mmu = OV5_FEAT(OV5_MMU_RADIX_300) | OV5_FEAT(OV5_MMU_HASH_300) | - OV5_FEAT(OV5_MMU_PROC_TBL) | OV5_FEAT(OV5_MMU_GTSE), + .mmu = 0, + .hash_ext = 0, + .radix_ext = 0, }, /* option vector 6: IBM PAPR hints */ @@ -990,6 +1007,92 @@ static int __init prom_count_smt_threads(void) } +static void __init prom_parse_mmu_model(u8 val, + struct platform_support *support) +{ + switch (val) { + case OV5_FEAT(OV5_MMU_DYNAMIC): + case OV5_FEAT(OV5_MMU_EITHER): /* Either Available */ + prom_debug("MMU - either supported\n"); + support->radix_mmu = !prom_radix_disable; + support->hash_mmu = true; + break; + case OV5_FEAT(OV5_MMU_RADIX): /* Only Radix */ + prom_debug("MMU - radix only\n"); + if (prom_radix_disable) { + /* + * If we __have__ to do radix, we're better off ignoring + * the command line rather than not booting. + */ + prom_printf("WARNING: Ignoring cmdline option disable_radix\n"); + } + support->radix_mmu = true; + break; + case OV5_FEAT(OV5_MMU_HASH): + prom_debug("MMU - hash only\n"); + support->hash_mmu = true; + break; + default: + prom_debug("Unknown mmu support option: 0x%x\n", val); + break; + } +} + +static void __init prom_parse_platform_support(u8 index, u8 val, + struct platform_support *support) +{ + switch (index) { + case OV5_INDX(OV5_MMU_SUPPORT): /* MMU Model */ + prom_parse_mmu_model(val & OV5_FEAT(OV5_MMU_SUPPORT), support); + break; + case OV5_INDX(OV5_RADIX_GTSE): /* Radix Extensions */ + if (val & OV5_FEAT(OV5_RADIX_GTSE)) { + prom_debug("Radix - GTSE supported\n"); + support->radix_gtse = true; + } + break; + } +} + +static void __init prom_check_platform_support(void) +{ + struct platform_support supported = { + .hash_mmu = false, + .radix_mmu = false, + .radix_gtse = false + }; + int prop_len = prom_getproplen(prom.chosen, + "ibm,arch-vec-5-platform-support"); + if (prop_len > 1) { + int i; + u8 vec[prop_len]; + prom_debug("Found ibm,arch-vec-5-platform-support, len: %d\n", + prop_len); + prom_getprop(prom.chosen, "ibm,arch-vec-5-platform-support", + &vec, sizeof(vec)); + for (i = 0; i < prop_len; i += 2) { + prom_debug("%d: index = 0x%x val = 0x%x\n", i / 2 + , vec[i] + , vec[i + 1]); + prom_parse_platform_support(vec[i], vec[i + 1], + &supported); + } + } + + if (supported.radix_mmu && supported.radix_gtse) { + /* Radix preferred - but we require GTSE for now */ + prom_debug("Asking for radix with GTSE\n"); + ibm_architecture_vec.vec5.mmu = OV5_FEAT(OV5_MMU_RADIX); + ibm_architecture_vec.vec5.radix_ext = OV5_FEAT(OV5_RADIX_GTSE); + } else if (supported.hash_mmu) { + /* Default to hash mmu (if we can) */ + prom_debug("Asking for hash\n"); + ibm_architecture_vec.vec5.mmu = OV5_FEAT(OV5_MMU_HASH); + } else { + /* We're probably on a legacy hypervisor */ + prom_debug("Assuming legacy hash support\n"); + } +} static void __init prom_send_capabilities(void) { @@ -997,6 +1100,9 @@ static void __init prom_send_capabilities(void) prom_arg_t ret; u32 cores; + /* Check ibm,arch-vec-5-platform-support and fixup vec5 if required */ + prom_check_platform_support(); + root = call_prom("open", 1, 1, ADDR("/")); if (root != 0) { /* We need to tell the FW about the number of cores we support. |