Crashkernel reservation on high memory depends on the MMU type. In particular, arch_reserve_crashkernel() needs to know whether the radix MMU is enabled when selecting the crashkernel reservation.
arch_reserve_crashkernel() is intentionally called early during boot. The crashkernel memory needs to be reserved before other components make memory reservations, as those reservations could interfere with finding a suitable region for the crashkernel at the required offset. Therefore, moving arch_reserve_crashkernel() to a later point is not a suitable solution. Instead, make the MMU type available before arch_reserve_crashkernel() is called. The MMU type is determined from the FDT and kernel configuration and is recorded in cur_cpu_spec->mmu_features. early_radix_enabled() uses cur_cpu_spec->mmu_features to determine whether the radix MMU is enabled. However, the MMU type discovery was previously performed as part of mmu_early_init_devtree(), which runs after arch_reserve_crashkernel(). Split the MMU type discovery from the rest of mmu_early_init_devtree() and perform it before arch_reserve_crashkernel(). This makes early_radix_enabled() usable from arch_reserve_crashkernel(), which will be used by the following patch to select the appropriate crashkernel reservation on high memory. Signed-off-by: Sourabh Jain <[email protected]> Reviewed-by: Ritesh Harjani (IBM) <[email protected]> --- arch/powerpc/include/asm/book3s/64/mmu.h | 1 + arch/powerpc/include/asm/mmu.h | 1 + arch/powerpc/kernel/prom.c | 29 +++++++++++++----------- arch/powerpc/mm/init_64.c | 26 +++++++++++++-------- 4 files changed, 34 insertions(+), 23 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h index 48631365b48c..d820640f2739 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu.h +++ b/arch/powerpc/include/asm/book3s/64/mmu.h @@ -208,6 +208,7 @@ extern int mmu_vmemmap_psize; /* MMU initialization */ void mmu_early_init_devtree(void); +void mmu_early_init_type(void); void hash__early_init_devtree(void); void radix__early_init_devtree(void); #ifdef CONFIG_PPC_PKEY diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h index 5f9c5d436e17..da0b498bd475 100644 --- a/arch/powerpc/include/asm/mmu.h +++ b/arch/powerpc/include/asm/mmu.h @@ -384,6 +384,7 @@ extern void early_init_mmu_secondary(void); extern void setup_initial_memory_limit(phys_addr_t first_memblock_base, phys_addr_t first_memblock_size); static inline void mmu_early_init_devtree(void) { } +static inline void mmu_early_init_type(void) { } static inline void pkey_early_init_devtree(void) {} diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 9ed9dde7d231..4fc53129e6ee 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -853,6 +853,22 @@ void __init early_init_devtree(void *params) if (PHYSICAL_START > MEMORY_START) memblock_reserve(MEMORY_START, int_vector_size); reserve_kdump_trampoline(); + + DBG("Scanning CPUs ...\n"); + + dt_cpu_ftrs_scan(); + + /* Retrieve CPU related informations from the flat tree + * (altivec support, boot CPU ID, ...) + */ + of_scan_flat_dt(early_init_dt_scan_cpus, NULL); + if (boot_cpuid < 0) { + printk("Failed to identify boot CPU !\n"); + BUG(); + } + + mmu_early_init_type(); + #if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP) /* * If we fail to reserve memory for firmware-assisted dump then @@ -884,19 +900,6 @@ void __init early_init_devtree(void *params) * FIXME .. and the initrd too? */ move_device_tree(); - DBG("Scanning CPUs ...\n"); - - dt_cpu_ftrs_scan(); - - /* Retrieve CPU related informations from the flat tree - * (altivec support, boot CPU ID, ...) - */ - of_scan_flat_dt(early_init_dt_scan_cpus, NULL); - if (boot_cpuid < 0) { - printk("Failed to identify boot CPU !\n"); - BUG(); - } - save_fscr_to_task(); #if defined(CONFIG_SMP) && defined(CONFIG_PPC64) diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c index 64f0df5bb5cd..4916ed230600 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -614,7 +614,8 @@ static void __init early_init_memory_block_size(void) of_scan_flat_dt(probe_memory_block_size, &memory_block_size); } -void __init mmu_early_init_devtree(void) + +void __init mmu_early_init_type(void) { bool hvmode = !!(mfmsr() & MSR_HV); @@ -626,6 +627,20 @@ void __init mmu_early_init_devtree(void) pr_warn("WARNING: Ignoring cmdline option disable_radix\n"); } + /* + * 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 (!hvmode) + early_check_vec5(); +} + +void __init mmu_early_init_devtree(void) +{ + bool hvmode = !!(mfmsr() & MSR_HV); + of_scan_flat_dt(dt_scan_mmu_pid_width, NULL); if (hvmode && !mmu_lpid_bits) { if (early_cpu_has_feature(CPU_FTR_ARCH_207S)) @@ -638,15 +653,6 @@ void __init mmu_early_init_devtree(void) 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 (!hvmode) - early_check_vec5(); - early_init_memory_block_size(); if (early_radix_enabled()) { -- 2.55.0
