summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/mm/init_64.c
diff options
context:
space:
mode:
authorSuraj Jitindar Singh <sjitindarsingh@gmail.com>2017-02-28 17:03:48 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2017-03-06 21:44:09 +1100
commit014d02cbf16b3106dc8e93281d2a9c189751ed5e (patch)
tree31f2cd87c238719b3d53492ac307db57ec2e935e /arch/powerpc/mm/init_64.c
parent12cc9fd6b2d8ee307a735b3b9faed0d17b719463 (diff)
downloadlinux-014d02cbf16b3106dc8e93281d2a9c189751ed5e.tar.bz2
powerpc: Update to new option-vector-5 format for CAS
On POWER9 the ibm,client-architecture-support (CAS) negotiation process has been updated to change how the host to guest negotiation is done for the new hash/radix mmu as well as the nest mmu, process tables and guest translation shootdown (GTSE). This is documented in the unreleased PAPR ACR "CAS option vector additions for P9". The host tells the guest which options it supports in ibm,arch-vec-5-platform-support. The guest then chooses a subset of these to request in the CAS call and these are agreed to in the ibm,architecture-vec-5 property of the chosen node. Thus we read ibm,arch-vec-5-platform-support and make our selection before calling CAS. We then parse the ibm,architecture-vec-5 property of the chosen node to check whether we should run as hash or radix. ibm,arch-vec-5-platform-support format: index value pairs: <index, val> ... <index, val> index: Option vector 5 byte number val: Some representation of supported values Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> [mpe: Don't print about unknown options, be consistent with OV5_FEAT] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/init_64.c')
-rw-r--r--arch/powerpc/mm/init_64.c36
1 files changed, 30 insertions, 6 deletions
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index 6aa3b76aa0d6..9be992083d2a 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -356,18 +356,42 @@ static void early_check_vec5(void)
unsigned long root, chosen;
int size;
const u8 *vec5;
+ u8 mmu_supported;
root = of_get_flat_dt_root();
chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
- if (chosen == -FDT_ERR_NOTFOUND)
+ if (chosen == -FDT_ERR_NOTFOUND) {
+ cur_cpu_spec->mmu_features &= ~MMU_FTR_TYPE_RADIX;
return;
+ }
vec5 = of_get_flat_dt_prop(chosen, "ibm,architecture-vec-5", &size);
- if (!vec5)
+ if (!vec5) {
+ cur_cpu_spec->mmu_features &= ~MMU_FTR_TYPE_RADIX;
return;
- if (size <= OV5_INDX(OV5_MMU_RADIX_300) ||
- !(vec5[OV5_INDX(OV5_MMU_RADIX_300)] & OV5_FEAT(OV5_MMU_RADIX_300)))
- /* Hypervisor doesn't support radix */
+ }
+ if (size <= OV5_INDX(OV5_MMU_SUPPORT)) {
cur_cpu_spec->mmu_features &= ~MMU_FTR_TYPE_RADIX;
+ return;
+ }
+
+ /* Check for supported configuration */
+ mmu_supported = vec5[OV5_INDX(OV5_MMU_SUPPORT)] &
+ OV5_FEAT(OV5_MMU_SUPPORT);
+ if (mmu_supported == OV5_FEAT(OV5_MMU_RADIX)) {
+ /* Hypervisor only supports radix - check enabled && GTSE */
+ if (!early_radix_enabled()) {
+ pr_warn("WARNING: Ignoring cmdline option disable_radix\n");
+ }
+ if (!(vec5[OV5_INDX(OV5_RADIX_GTSE)] &
+ OV5_FEAT(OV5_RADIX_GTSE))) {
+ pr_warn("WARNING: Hypervisor doesn't support RADIX with GTSE\n");
+ }
+ /* Do radix anyway - the hypervisor said we had to */
+ cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
+ } else if (mmu_supported == OV5_FEAT(OV5_MMU_HASH)) {
+ /* Hypervisor only supports hash - disable radix */
+ cur_cpu_spec->mmu_features &= ~MMU_FTR_TYPE_RADIX;
+ }
}
void __init mmu_early_init_devtree(void)
@@ -383,7 +407,7 @@ void __init mmu_early_init_devtree(void)
* even though the ibm,architecture-vec-5 property created by
* skiboot doesn't have the necessary bits set.
*/
- if (early_radix_enabled() && !(mfmsr() & MSR_HV))
+ if (!(mfmsr() & MSR_HV))
early_check_vec5();
if (early_radix_enabled())