Thread (27 messages) flat view 27 messages, 2 authors, 2021-08-02

Re: [boot-wrapper PATCH 08/12] Consistently use logical CPU IDs

From: Andre Przywara <andre.przywara@arm.com>
Date: 2021-07-30 17:41:42

On Thu, 29 Jul 2021 16:20:46 +0100
Mark Rutland [off-list ref] wrote:
In some places we assume that the cpu with MPIDR_EL1.Aff* == 0 is the
same as logical CPU 0. While this is almost certainly true, it would be
best to consistently use the ligical ID.
                               logical

Indeed, and I think can we can configure the model to have the primary
CPU with an MPIDR != 0.
Add a new `this_cpu_logical_id()` helper, and use this in preference to
checking the MPIDR_EL1.Aff* bits directly.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>

Cheers,
Andre
quoted hunk ↗ jump to hunk
---
 gic-v3.c      | 4 +---
 gic.c         | 3 +--
 include/cpu.h | 2 ++
 psci.c        | 5 ++---
 4 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/gic-v3.c b/gic-v3.c
index ae2d2bc..62f9676 100644
--- a/gic-v3.c
+++ b/gic-v3.c
@@ -101,8 +101,6 @@ void gic_secure_init_primary(void)
 
 void gic_secure_init(void)
 {
-	uint32_t cpu = read_mpidr();
-
 	uint32_t sre;
 
 	/*
@@ -113,7 +111,7 @@ void gic_secure_init(void)
 	if (!has_gicv3_sysreg())
 		return;
 
-	if (cpu == 0)
+	if (this_cpu_logical_id() == 0)
 		gic_secure_init_primary();
 
 	sre = gic_read_icc_sre();
diff --git a/gic.c b/gic.c
index a84779e..04d4289 100644
--- a/gic.c
+++ b/gic.c
@@ -31,14 +31,13 @@ void gic_secure_init(void)
 {
 	unsigned int i;
 
-	uint32_t cpu = read_mpidr();
 	void *gicd_base = (void *)GIC_DIST_BASE;
 	void *gicc_base = (void *)GIC_CPU_BASE;
 
 	/* Set local interrupts to Group 1 (those fields are banked) */
 	raw_writel(~0, gicd_base + GICD_IGROUPRn);
 
-	if (cpu == 0) {
+	if (this_cpu_logical_id() == 0) {
 		uint32_t typer = raw_readl(gicd_base + GICD_TYPER);
 
 		/* Set SPIs to Group 1 */
diff --git a/include/cpu.h b/include/cpu.h
index 704d6d8..4bfb172 100644
--- a/include/cpu.h
+++ b/include/cpu.h
@@ -25,5 +25,7 @@
 
 unsigned int find_logical_id(unsigned long mpidr);
 
+#define this_cpu_logical_id()	find_logical_id(read_mpidr())
+
 #endif /* !__ASSEMBLY__ */
 #endif
diff --git a/psci.c b/psci.c
index e5d54b7..df5b0f2 100644
--- a/psci.c
+++ b/psci.c
@@ -35,7 +35,7 @@ static int psci_cpu_on(unsigned long target_mpidr, unsigned long address)
 {
 	int ret;
 	unsigned int cpu = find_logical_id(target_mpidr);
-	unsigned int this_cpu = find_logical_id(read_mpidr());
+	unsigned int this_cpu = this_cpu_logical_id();
 
 	if (cpu == MPIDR_INVALID)
 		return PSCI_RET_INVALID_PARAMETERS;
@@ -49,8 +49,7 @@ static int psci_cpu_on(unsigned long target_mpidr, unsigned long address)
 
 static int psci_cpu_off(void)
 {
-	unsigned long mpidr = read_mpidr();
-	unsigned int cpu = find_logical_id(mpidr);
+	unsigned int cpu = this_cpu_logical_id();
 
 	if (cpu == MPIDR_INVALID)
 		return PSCI_RET_DENIED;

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