lkml.org 
[lkml]   [2016]   [Feb]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 2/8] arm64: HWCAP: Split COMPAT HWCAP table entries
Date
In order to handle systems which do not support 32bit at EL0,
split the COMPAT HWCAP entries into a separate table which can
be processed, only if the support is available.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
arch/arm64/kernel/cpufeature.c | 78 ++++++++++++++++++++++++----------------
1 file changed, 47 insertions(+), 31 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index a3c254b..b88cbef 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -691,6 +691,10 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS),
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP),
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
+ {},
+};
+
+static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
#ifdef CONFIG_COMPAT
HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
@@ -746,10 +750,9 @@ static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
return rc;
}

-static void __init setup_elf_hwcaps(void)
+static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
{
int i;
- const struct arm64_cpu_capabilities *hwcaps = arm64_elf_hwcaps;

for (i = 0; hwcaps[i].desc; i++)
if (hwcaps[i].matches(&hwcaps[i]))
@@ -850,29 +853,26 @@ static void check_early_cpu_features(void)
verify_cpu_asid_bits();
}

-/*
- * Run through the enabled system capabilities and enable() it on this CPU.
- * The capabilities were decided based on the available CPUs at the boot time.
- * Any new CPU should match the system wide status of the capability. If the
- * new CPU doesn't have a capability which the system now has enabled, we
- * cannot do anything to fix it up and could cause unexpected failures. So
- * we park the CPU.
- */
-void verify_local_cpu_capabilities(void)
+static void
+verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps)
{
int i;
- const struct arm64_cpu_capabilities *caps;

- check_early_cpu_features();
-
- /*
- * If we haven't computed the system capabilities, there is nothing
- * to verify.
- */
- if (!sys_caps_initialised)
- return;
+ for (i = 0; caps[i].desc; i++) {
+ if (!cpus_have_elf_hwcap(&caps[i]))
+ continue;
+ if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) {
+ pr_crit("CPU%d: missing HWCAP: %s\n",
+ smp_processor_id(), caps[i].desc);
+ cpu_die_early();
+ }
+ }
+}

- caps = arm64_features;
+static void
+verify_local_cpu_features(const struct arm64_cpu_capabilities *caps)
+{
+ int i;
for (i = 0; caps[i].desc; i++) {
if (!cpus_have_cap(caps[i].capability) || !caps[i].sys_reg)
continue;
@@ -888,16 +888,31 @@ void verify_local_cpu_capabilities(void)
if (caps[i].enable)
caps[i].enable(NULL);
}
+}

- for (i = 0, caps = arm64_elf_hwcaps; caps[i].desc; i++) {
- if (!cpus_have_elf_hwcap(&caps[i]))
- continue;
- if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) {
- pr_crit("CPU%d: missing HWCAP: %s\n",
- smp_processor_id(), caps[i].desc);
- cpu_die_early();
- }
- }
+/*
+ * Run through the enabled system capabilities and enable() it on this CPU.
+ * The capabilities were decided based on the available CPUs at the boot time.
+ * Any new CPU should match the system wide status of the capability. If the
+ * new CPU doesn't have a capability which the system now has enabled, we
+ * cannot do anything to fix it up and could cause unexpected failures. So
+ * we park the CPU.
+ */
+void verify_local_cpu_capabilities(void)
+{
+
+ check_early_cpu_features();
+
+ /*
+ * If we haven't computed the system capabilities, there is nothing
+ * to verify.
+ */
+ if (!sys_caps_initialised)
+ return;
+
+ verify_local_cpu_features(arm64_features);
+ verify_local_elf_hwcaps(arm64_elf_hwcaps);
+ verify_local_elf_hwcaps(compat_elf_hwcaps);
}

static void __init setup_feature_capabilities(void)
@@ -913,7 +928,8 @@ void __init setup_cpu_features(void)

/* Set the CPU feature capabilies */
setup_feature_capabilities();
- setup_elf_hwcaps();
+ setup_elf_hwcaps(arm64_elf_hwcaps);
+ setup_elf_hwcaps(compat_elf_hwcaps);

/* Advertise that we have computed the system capabilities */
set_sys_caps_initialised();
--
1.7.9.5
\
 
 \ /
  Last update: 2016-02-25 11:41    [W:1.028 / U:0.956 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site