@@ -7,6 +7,7 @@ subdir-$(CONFIG_ACPI) += acpi
obj-$(CONFIG_ALTERNATIVE) += alternative.o
obj-y += bootfdt.o
obj-y += cpu.o
+obj-y += cpuerrata.o
obj-y += cpufeature.o
obj-y += decode.o
obj-y += device.o
new file mode 100644
@@ -0,0 +1,26 @@
+#include <xen/config.h>
+#include <asm/cpufeature.h>
+#include <asm/cpuerrata.h>
+
+#define MIDR_RANGE(model, min, max) \
+ .matches = is_affected_midr_range, \
+ .midr_model = model, \
+ .midr_range_min = min, \
+ .midr_range_max = max
+
+static bool_t __maybe_unused
+is_affected_midr_range(const struct arm_cpu_capabilities *entry)
+{
+ return MIDR_IS_CPU_MODEL_RANGE(boot_cpu_data.midr.bits, entry->midr_model,
+ entry->midr_range_min,
+ entry->midr_range_max);
+}
+
+static const struct arm_cpu_capabilities arm_errata[] = {
+ {},
+};
+
+void check_local_cpu_errata(void)
+{
+ update_cpu_capabilities(arm_errata, "enabled workaround for");
+}
@@ -43,6 +43,7 @@
#include <asm/current.h>
#include <asm/setup.h>
#include <asm/gic.h>
+#include <asm/cpuerrata.h>
#include <asm/cpufeature.h>
#include <asm/platform.h>
#include <asm/procinfo.h>
@@ -171,6 +172,8 @@ static void __init processor_id(void)
}
processor_setup();
+
+ check_local_cpu_errata();
}
void dt_unreserved_regions(paddr_t s, paddr_t e,
@@ -29,6 +29,7 @@
#include <xen/timer.h>
#include <xen/irq.h>
#include <xen/console.h>
+#include <asm/cpuerrata.h>
#include <asm/gic.h>
#include <asm/psci.h>
#include <asm/acpi.h>
@@ -317,6 +318,8 @@ void start_secondary(unsigned long boot_phys_offset,
local_irq_enable();
local_abort_enable();
+ check_local_cpu_errata();
+
printk(XENLOG_DEBUG "CPU %u booted.\n", smp_processor_id());
startup_cpu_idle_loop();
new file mode 100644
@@ -0,0 +1,6 @@
+#ifndef __ARM_CPUERRATA_H
+#define __ARM_CPUERRATA_H
+
+void check_local_cpu_errata(void);
+
+#endif /* __ARM_CPUERRATA_H */
@@ -66,6 +66,12 @@ struct arm_cpu_capabilities {
const char *desc;
u16 capability;
bool_t (*matches)(const struct arm_cpu_capabilities *);
+ union {
+ struct { /* To be used for eratum handling only */
+ u32 midr_model;
+ u32 midr_range_min, midr_range_max;
+ };
+ };
};
void update_cpu_capabilities(const struct arm_cpu_capabilities *caps,
After each CPU has been started, we iterate through a list of CPU errata to detect CPUs which need from hypervisor code patches. For each bug there is a function which check if that a particular CPU is affected. This needs to be done on every CPUs to cover heterogenous system properly. If a certain erratum has been detected, the capability bit will be set. In the case the erratum requires code patching, this will be triggered by the call to apply_alternatives. The code is based on the file arch/arm64/kernel/cpu_errata.c in Linux v4.6-rc3. Signed-off-by: Julien Grall <julien.grall@arm.com> --- Changes in v3: - Move update_cpu_capabilities in a separate patch - Update the commit message to mention that workaround may not require code patching. Changes in v2: - Use XENLOG_INFO for the loglevel of the message --- xen/arch/arm/Makefile | 1 + xen/arch/arm/cpuerrata.c | 26 ++++++++++++++++++++++++++ xen/arch/arm/setup.c | 3 +++ xen/arch/arm/smpboot.c | 3 +++ xen/include/asm-arm/cpuerrata.h | 6 ++++++ xen/include/asm-arm/cpufeature.h | 6 ++++++ 6 files changed, 45 insertions(+) create mode 100644 xen/arch/arm/cpuerrata.c create mode 100644 xen/include/asm-arm/cpuerrata.h