diff options
Diffstat (limited to 'arch/powerpc/mm/init_64.c')
| -rw-r--r-- | arch/powerpc/mm/init_64.c | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c index 386be136026e..3e5f9ac9dded 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -370,6 +370,9 @@ void register_page_bootmem_memmap(unsigned long section_nr, #endif /* CONFIG_SPARSEMEM_VMEMMAP */ #ifdef CONFIG_PPC_BOOK3S_64 +unsigned int mmu_lpid_bits; +unsigned int mmu_pid_bits; + static bool disable_radix = !IS_ENABLED(CONFIG_PPC_RADIX_MMU_DEFAULT); static int __init parse_disable_radix(char *p) @@ -437,19 +440,60 @@ static void __init early_check_vec5(void) } } +static int __init dt_scan_mmu_pid_width(unsigned long node, + const char *uname, int depth, + void *data) +{ + int size = 0; + const __be32 *prop; + const char *type = of_get_flat_dt_prop(node, "device_type", NULL); + + /* We are scanning "cpu" nodes only */ + if (type == NULL || strcmp(type, "cpu") != 0) + return 0; + + /* Find MMU LPID, PID register size */ + prop = of_get_flat_dt_prop(node, "ibm,mmu-lpid-bits", &size); + if (prop && size == 4) + mmu_lpid_bits = be32_to_cpup(prop); + + prop = of_get_flat_dt_prop(node, "ibm,mmu-pid-bits", &size); + if (prop && size == 4) + mmu_pid_bits = be32_to_cpup(prop); + + if (!mmu_pid_bits && !mmu_lpid_bits) + return 0; + + return 1; +} + void __init mmu_early_init_devtree(void) { + bool hvmode = !!(mfmsr() & MSR_HV); + /* Disable radix mode based on kernel command line. */ if (disable_radix) cur_cpu_spec->mmu_features &= ~MMU_FTR_TYPE_RADIX; + of_scan_flat_dt(dt_scan_mmu_pid_width, NULL); + if (hvmode && !mmu_lpid_bits) { + if (early_cpu_has_feature(CPU_FTR_ARCH_207S)) + mmu_lpid_bits = 12; /* POWER8-10 */ + else + mmu_lpid_bits = 10; /* POWER7 */ + } + if (!mmu_pid_bits) { + if (early_cpu_has_feature(CPU_FTR_ARCH_300)) + mmu_pid_bits = 20; /* POWER9-10 */ + } + /* * Check /chosen/ibm,architecture-vec-5 if running as a guest. * When running bare-metal, we can use radix if we like * even though the ibm,architecture-vec-5 property created by * skiboot doesn't have the necessary bits set. */ - if (!(mfmsr() & MSR_HV)) + if (!hvmode) early_check_vec5(); if (early_radix_enabled()) { |