firmware: qcom: scm: Add support for MC boot address API

It looks like the old QCOM_SCM_BOOT_SET_ADDR API is broken on some
MSM8916 firmware versions that implement the newer SMC32 calling
convention. It just returns -EINVAL no matter which arguments are
being passed.

This does not cause any problems downstream because it first tries
to use the new multi-cluster API replacement which is working fine.

Implement support for the multi-cluster variant of the SCM call
by attempting it first but still fallback to the old call in case
of an error. Also, to be absolutely sure only use the multi-cluster
variant with the SMC calling convention since older platforms should
not need this.

Signed-off-by: Stephan Gerhold <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: stephan-gh

drivers/firmware/qcom_scm.c

@@ -17,6 +17,8 @@
 #include <linux/reset-controller.h>
 #include <linux/arm-smccc.h>
 
+#include <asm/smp_plat.h>
+
 #include "qcom_scm.h"
 
 static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT);
@@ -260,15 +262,36 @@ 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_mc(void *entry, const cpumask_t *cpus,
+				       unsigned int flags)
+{
+	struct qcom_scm_desc desc = {
+		.svc = QCOM_SCM_SVC_BOOT,
+		.cmd = QCOM_SCM_BOOT_SET_ADDR_MC,
+		.owner = ARM_SMCCC_OWNER_SIP,
+		.arginfo = QCOM_SCM_ARGS(6),
+	};
+	unsigned int cpu;
+	u64 map;
+
+	/* Need a device for DMA of the additional arguments */
+	if (!__scm || __get_convention() == SMC_CONVENTION_LEGACY)
+		return -EOPNOTSUPP;
+
+	desc.args[0] = virt_to_phys(entry);
+	for_each_cpu(cpu, cpus) {
+		map = cpu_logical_map(cpu);
+		desc.args[1] |= BIT(MPIDR_AFFINITY_LEVEL(map, 0));
+		desc.args[2] |= BIT(MPIDR_AFFINITY_LEVEL(map, 1));
+		desc.args[3] |= BIT(MPIDR_AFFINITY_LEVEL(map, 2));
+	}
+	desc.args[4] = ~0ULL; /* Reserved for affinity level 3 */
+	desc.args[5] = flags;
+
+	return qcom_scm_call(__scm->dev, &desc, NULL);
+}
+
+static int __qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
 {
 	int ret;
 	int flags = 0;
@@ -304,17 +327,28 @@ int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
 
 	return ret;
 }
-EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
 
 /**
- * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
+ * 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 cold boot address of the cpus. Any cpu outside the supported
- * range would be removed from the cpu present mask.
+ * 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_cold_boot_addr(void *entry, const cpumask_t *cpus)
+int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
+{
+	if (!cpus || cpumask_empty(cpus))
+		return -EINVAL;
+
+	if (__qcom_scm_set_boot_addr_mc(entry, cpus, QCOM_SCM_BOOT_MC_FLAG_WARMBOOT))
+		/* Fallback to old SCM call */
+		return __qcom_scm_set_warm_boot_addr(entry, cpus);
+	return 0;
+}
+EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
+
+static int __qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
 {
 	int flags = 0;
 	int cpu;
@@ -331,9 +365,6 @@ int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
 		.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];
@@ -346,6 +377,25 @@ int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
 
 	return qcom_scm_call_atomic(__scm ? __scm->dev : NULL, &desc, NULL);
 }
+
+/**
+ * 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)
+{
+	if (!cpus || cpumask_empty(cpus))
+		return -EINVAL;
+
+	if (__qcom_scm_set_boot_addr_mc(entry, cpus, QCOM_SCM_BOOT_MC_FLAG_COLDBOOT))
+		/* Fallback to old SCM call */
+		return __qcom_scm_set_cold_boot_addr(entry, cpus);
+	return 0;
+}
 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
 
 /**

drivers/firmware/qcom_scm.h

@@ -78,8 +78,12 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
 #define QCOM_SCM_BOOT_SET_ADDR		0x01
 #define QCOM_SCM_BOOT_TERMINATE_PC	0x02
 #define QCOM_SCM_BOOT_SET_DLOAD_MODE	0x10
+#define QCOM_SCM_BOOT_SET_ADDR_MC	0x11
 #define QCOM_SCM_BOOT_SET_REMOTE_STATE	0x0a
 #define QCOM_SCM_FLUSH_FLAG_MASK	0x3
+#define QCOM_SCM_BOOT_MC_FLAG_AARCH64	BIT(0)
+#define QCOM_SCM_BOOT_MC_FLAG_COLDBOOT	BIT(1)
+#define QCOM_SCM_BOOT_MC_FLAG_WARMBOOT	BIT(2)
 
 #define QCOM_SCM_SVC_PIL		0x02
 #define QCOM_SCM_PIL_PAS_INIT_IMAGE	0x01