diff options
Diffstat (limited to 'arch/powerpc/mm/pgtable-radix.c')
| -rw-r--r-- | arch/powerpc/mm/pgtable-radix.c | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index 5cc50d47ce3f..671a45d86c18 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -25,6 +25,9 @@ #include <trace/events/thp.h> +unsigned int mmu_pid_bits; +unsigned int mmu_base_pid; + static int native_register_process_table(unsigned long base, unsigned long pg_sz, unsigned long table_size) { @@ -261,11 +264,34 @@ static void __init radix_init_pgtable(void) for_each_memblock(memory, reg) WARN_ON(create_physical_mapping(reg->base, reg->base + reg->size)); + + /* Find out how many PID bits are supported */ + if (cpu_has_feature(CPU_FTR_HVMODE)) { + if (!mmu_pid_bits) + mmu_pid_bits = 20; +#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE + /* + * When KVM is possible, we only use the top half of the + * PID space to avoid collisions between host and guest PIDs + * which can cause problems due to prefetch when exiting the + * guest with AIL=3 + */ + mmu_base_pid = 1 << (mmu_pid_bits - 1); +#else + mmu_base_pid = 1; +#endif + } else { + /* The guest uses the bottom half of the PID space */ + if (!mmu_pid_bits) + mmu_pid_bits = 19; + mmu_base_pid = 1; + } + /* * Allocate Partition table and process table for the * host. */ - BUILD_BUG_ON_MSG((PRTB_SIZE_SHIFT > 36), "Process table size too large."); + BUG_ON(PRTB_SIZE_SHIFT > 36); process_tb = early_alloc_pgtable(1UL << PRTB_SIZE_SHIFT); /* * Fill in the process table. @@ -339,6 +365,12 @@ static int __init radix_dt_scan_page_sizes(unsigned long node, if (type == NULL || strcmp(type, "cpu") != 0) return 0; + /* Find MMU PID size */ + prop = of_get_flat_dt_prop(node, "ibm,mmu-pid-bits", &size); + if (prop && size == 4) + mmu_pid_bits = be32_to_cpup(prop); + + /* Grab page size encodings */ prop = of_get_flat_dt_prop(node, "ibm,processor-radix-AP-encodings", &size); if (!prop) return 0; |