From 029ab30b4c0a7ec587eece1ec07c3981fdff2bed Mon Sep 17 00:00:00 2001 From: Bharata B Rao Date: Fri, 3 Jul 2020 11:06:06 +0530 Subject: powerpc/mm: Enable radix GTSE only if supported. Make GTSE an MMU feature and enable it by default for radix. However for guest, conditionally enable it if hypervisor supports it via OV5 vector. Let prom_init ask for radix GTSE only if the support exists. Having GTSE as an MMU feature will make it easy to enable radix without GTSE. Currently radix assumes GTSE is enabled by default. Signed-off-by: Bharata B Rao Reviewed-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200703053608.12884-2-bharata@linux.ibm.com --- arch/powerpc/kernel/prom_init.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'arch/powerpc/kernel/prom_init.c') diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c index 90c604d00b7d..cbc605cfdec0 100644 --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -1336,12 +1336,15 @@ static void __init prom_check_platform_support(void) } } - if (supported.radix_mmu && supported.radix_gtse && - IS_ENABLED(CONFIG_PPC_RADIX_MMU)) { - /* Radix preferred - but we require GTSE for now */ - prom_debug("Asking for radix with GTSE\n"); + if (supported.radix_mmu && IS_ENABLED(CONFIG_PPC_RADIX_MMU)) { + /* Radix preferred - Check if GTSE is also supported */ + prom_debug("Asking for radix\n"); ibm_architecture_vec.vec5.mmu = OV5_FEAT(OV5_MMU_RADIX); - ibm_architecture_vec.vec5.radix_ext = OV5_FEAT(OV5_RADIX_GTSE); + if (supported.radix_gtse) + ibm_architecture_vec.vec5.radix_ext = + OV5_FEAT(OV5_RADIX_GTSE); + else + prom_debug("Radix GTSE isn't supported\n"); } else if (supported.hash_mmu) { /* Default to hash mmu (if we can) */ prom_debug("Asking for hash\n"); -- cgit v1.2.3-59-g8ed1b