When running on SoC with multiple clusters, the boot CPU may
not be fixed, saying booting from cluster A or cluster B.
Add a API that can return the udevice for current boot CPU.
Cpu driver needs to implement is_current_cpu interface for this
feature, otherwise the API only returns the first udevice in
cpu uclass.
Reviewed-by: Simon Glass <s...@chromium.org>
Signed-off-by: Peng Fan <peng....@nxp.com>
Signed-off-by: Ye Li <ye...@nxp.com>
---
V3:
Drop ops check. Add R-b
V2:
Per Simon's comment,
- Add cpu_is_current
- use uclass_foreach_dev_probe
- Update code comment
drivers/cpu/cpu-uclass.c | 34 ++++++++++++++++++++++++++++++++++
include/cpu.h | 23 +++++++++++++++++++++++
2 files changed, 57 insertions(+)
diff --git a/drivers/cpu/cpu-uclass.c b/drivers/cpu/cpu-uclass.c
index 457f77b7c8..8352e2eb0b 100644
--- a/drivers/cpu/cpu-uclass.c
+++ b/drivers/cpu/cpu-uclass.c
@@ -10,6 +10,7 @@
#include <errno.h>
#include <dm/lists.h>
#include <dm/root.h>
+#include <linux/err.h>
int cpu_probe_all(void)
{
@@ -34,6 +35,39 @@ int cpu_probe_all(void)
return 0;
}
+int cpu_is_current(struct udevice *cpu)
+{
+ struct cpu_ops *ops = cpu_get_ops(cpu);
+
+ if (ops->is_current) {
+ if (ops->is_current(cpu))
+ return 1;
+ }
+
+ return -ENOSYS;
+}
+
+struct udevice *cpu_get_current_dev(void)
+{
+ struct udevice *cpu;
+ int ret;
+
+ uclass_foreach_dev_probe(UCLASS_CPU, cpu) {
+ if (cpu_is_current(cpu) > 0)
+ return cpu;
+ }
+
+ /* If can't find current cpu device, use the first dev instead */
+ ret = uclass_first_device_err(UCLASS_CPU, &cpu);
+ if (ret) {
+ debug("%s: Could not get CPU device (err = %d)\n",
+ __func__, ret);
+ return NULL;
+ }
+
+ return cpu;
+}
+
int cpu_get_desc(struct udevice *dev, char *buf, int size)
{
struct cpu_ops *ops = cpu_get_ops(dev);
diff --git a/include/cpu.h b/include/cpu.h
index 6b1b6b37b3..2f283fe244 100644
--- a/include/cpu.h
+++ b/include/cpu.h
@@ -89,6 +89,15 @@ struct cpu_ops {
* @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
*/
int (*get_vendor)(struct udevice *dev, char *buf, int size);
+
+ /**
+ * is_current() - Check if the CPU that U-Boot is currently running from
+ *
+ * @dev: Device to check (UCLASS_CPU)
+ * @return 1 if the CPU that U-Boot is currently running from, 0
+ * if not.
+ */
+ int (*is_current)(struct udevice *dev);
};
#define cpu_get_ops(dev) ((struct cpu_ops *)(dev)->driver->ops)
@@ -137,4 +146,18 @@ int cpu_get_vendor(struct udevice *dev, char *buf, int
size);
*/
int cpu_probe_all(void);
+/**
+ * cpu_is_current() - Check if the CPU that U-Boot is currently running from
+ *
+ * Return: 1 if yes, - 0 if not
+ */
+int cpu_is_current(struct udevice *cpu);
+
+/**
+ * cpu_get_current_dev() - Get CPU udevice for current CPU
+ *
+ * Return: udevice if OK, - NULL on error
+ */
+struct udevice *cpu_get_current_dev(void);
+
#endif
--
2.16.4
