[PATCH v3 2/4] firmware: qcom: scm: Simplify set_cold/warm_boot_addr()
Stephan Gerhold
stephan at gerhold.net
Wed Dec 1 05:05:03 PST 2021
The qcom_scm_set_cold/warm_boot_addr() implementations have a lot of
functionality that is actually not used.
For example, set_warm_boot_addr() caches the last used entry address
and skips making the SCM call when the entry address is unchanged.
But there is actually just a single call of qcom_scm_set_warm_boot_addr()
in the whole kernel tree, which always configures the entry address
to cpu_resume_arm().
Simplify this by having a single qcom_scm_set_boot_addr() function
for both cold and warm boot address. This is totally sufficient for
the functionality supported in the mainline tree.
Signed-off-by: Stephan Gerhold <stephan at gerhold.net>
---
drivers/firmware/qcom_scm.c | 105 +++++++++---------------------------
drivers/firmware/qcom_scm.h | 1 +
2 files changed, 27 insertions(+), 79 deletions(-)
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 7db8066b19fd..e0fca80bf6fc 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -49,26 +49,12 @@ struct qcom_scm_mem_map_info {
__le64 mem_size;
};
-#define QCOM_SCM_FLAG_COLDBOOT_CPU0 0x00
-#define QCOM_SCM_FLAG_COLDBOOT_CPU1 0x01
-#define QCOM_SCM_FLAG_COLDBOOT_CPU2 0x08
-#define QCOM_SCM_FLAG_COLDBOOT_CPU3 0x20
-
-#define QCOM_SCM_FLAG_WARMBOOT_CPU0 0x04
-#define QCOM_SCM_FLAG_WARMBOOT_CPU1 0x02
-#define QCOM_SCM_FLAG_WARMBOOT_CPU2 0x10
-#define QCOM_SCM_FLAG_WARMBOOT_CPU3 0x40
-
-struct qcom_scm_wb_entry {
- int flag;
- void *entry;
+/* Each bit configures cold/warm boot address for one of the 4 CPUs */
+static const u8 qcom_scm_cpu_cold_bits[QCOM_SCM_BOOT_MAX_CPUS] = {
+ 0, BIT(0), BIT(3), BIT(5)
};
-
-static struct qcom_scm_wb_entry qcom_scm_wb[] = {
- { .flag = QCOM_SCM_FLAG_WARMBOOT_CPU0 },
- { .flag = QCOM_SCM_FLAG_WARMBOOT_CPU1 },
- { .flag = QCOM_SCM_FLAG_WARMBOOT_CPU2 },
- { .flag = QCOM_SCM_FLAG_WARMBOOT_CPU3 },
+static const u8 qcom_scm_cpu_warm_bits[QCOM_SCM_BOOT_MAX_CPUS] = {
+ BIT(2), BIT(1), BIT(4), BIT(6)
};
static const char * const qcom_scm_convention_names[] = {
@@ -260,49 +246,41 @@ static bool __qcom_scm_is_call_available(struct device *dev, u32 svc_id,
return ret ? false : !!res.result[0];
}
-/**
- * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
- * @entry: Entry point function for the cpus
- * @cpus: The cpumask of cpus that will use the entry point
- *
- * Set the Linux entry point for the SCM to transfer control to when coming
- * out of a power down. CPU power down may be executed on cpuidle or hotplug.
- */
-int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
+static int qcom_scm_set_boot_addr(void *entry, const cpumask_t *cpus,
+ const u8 *cpu_bits)
{
- int ret;
- int flags = 0;
int cpu;
+ unsigned int flags = 0;
struct qcom_scm_desc desc = {
.svc = QCOM_SCM_SVC_BOOT,
.cmd = QCOM_SCM_BOOT_SET_ADDR,
.arginfo = QCOM_SCM_ARGS(2),
+ .owner = ARM_SMCCC_OWNER_SIP,
};
- /*
- * Reassign only if we are switching from hotplug entry point
- * to cpuidle entry point or vice versa.
- */
for_each_cpu(cpu, cpus) {
- if (entry == qcom_scm_wb[cpu].entry)
- continue;
- flags |= qcom_scm_wb[cpu].flag;
+ if (cpu >= QCOM_SCM_BOOT_MAX_CPUS)
+ return -EINVAL;
+ flags |= cpu_bits[cpu];
}
- /* No change in entry function */
- if (!flags)
- return 0;
-
desc.args[0] = flags;
desc.args[1] = virt_to_phys(entry);
- ret = qcom_scm_call(__scm->dev, &desc, NULL);
- if (!ret) {
- for_each_cpu(cpu, cpus)
- qcom_scm_wb[cpu].entry = entry;
- }
+ return qcom_scm_call_atomic(__scm ? __scm->dev : NULL, &desc, NULL);
+}
- return ret;
+/**
+ * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
+ * @entry: Entry point function for the cpus
+ * @cpus: The cpumask of cpus that will use the entry point
+ *
+ * Set the Linux entry point for the SCM to transfer control to when coming
+ * out of a power down. CPU power down may be executed on cpuidle or hotplug.
+ */
+int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
+{
+ return qcom_scm_set_boot_addr(entry, cpus, qcom_scm_cpu_warm_bits);
}
EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
@@ -310,41 +288,10 @@ EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
* qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
* @entry: Entry point function for the cpus
* @cpus: The cpumask of cpus that will use the entry point
- *
- * Set the cold boot address of the cpus. Any cpu outside the supported
- * range would be removed from the cpu present mask.
*/
int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
{
- int flags = 0;
- int cpu;
- int scm_cb_flags[] = {
- QCOM_SCM_FLAG_COLDBOOT_CPU0,
- QCOM_SCM_FLAG_COLDBOOT_CPU1,
- QCOM_SCM_FLAG_COLDBOOT_CPU2,
- QCOM_SCM_FLAG_COLDBOOT_CPU3,
- };
- struct qcom_scm_desc desc = {
- .svc = QCOM_SCM_SVC_BOOT,
- .cmd = QCOM_SCM_BOOT_SET_ADDR,
- .arginfo = QCOM_SCM_ARGS(2),
- .owner = ARM_SMCCC_OWNER_SIP,
- };
-
- if (!cpus || cpumask_empty(cpus))
- return -EINVAL;
-
- for_each_cpu(cpu, cpus) {
- if (cpu < ARRAY_SIZE(scm_cb_flags))
- flags |= scm_cb_flags[cpu];
- else
- set_cpu_present(cpu, false);
- }
-
- desc.args[0] = flags;
- desc.args[1] = virt_to_phys(entry);
-
- return qcom_scm_call_atomic(__scm ? __scm->dev : NULL, &desc, NULL);
+ return qcom_scm_set_boot_addr(entry, cpus, qcom_scm_cpu_cold_bits);
}
EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
index d92156ceb3ac..fd7d2a5f3e70 100644
--- a/drivers/firmware/qcom_scm.h
+++ b/drivers/firmware/qcom_scm.h
@@ -80,6 +80,7 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
#define QCOM_SCM_BOOT_SET_DLOAD_MODE 0x10
#define QCOM_SCM_BOOT_SET_REMOTE_STATE 0x0a
#define QCOM_SCM_FLUSH_FLAG_MASK 0x3
+#define QCOM_SCM_BOOT_MAX_CPUS 4
#define QCOM_SCM_SVC_PIL 0x02
#define QCOM_SCM_PIL_PAS_INIT_IMAGE 0x01
--
2.34.1
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