uclass: cpu: Add new API to get udevice for current CPU

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 <sjg@chromium.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
This commit is contained in:
Peng Fan 2020-05-03 21:58:47 +08:00 committed by Stefano Babic
parent d8e775539e
commit 4c809aee50
2 changed files with 57 additions and 0 deletions

View File

@ -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);

View File

@ -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