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powerpc: Update to new option-vector-5 format for CAS

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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>
This commit is contained in:
Suraj Jitindar Singh
2017-02-28 17:03:48 +11:00
committed by Michael Ellerman
parent 12cc9fd6b2
commit 014d02cbf1
3 changed files with 153 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
arch/powerpc/mm/init_64.c
View File

@@ -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)
return;
vec5 = of_get_flat_dt_prop(chosen, "ibm,architecture-vec-5", &size);
if (!vec5)
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 (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) {
cur_cpu_spec->mmu_features &= ~MMU_FTR_TYPE_RADIX;
return;
}
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())