@@ -34,9 +34,9 @@ struct sbi_hsm_device {
* the hart resumes normal execution.
*
* For successful non-retentive suspend, the hart will resume from
- * specified resume address
+ * the warm boot entry point.
*/
- int (*hart_suspend)(u32 suspend_type, ulong raddr);
+ int (*hart_suspend)(u32 suspend_type);
/**
* Perform platform-specific actions to resume from a suspended state.
@@ -171,10 +171,10 @@ static int hsm_device_hart_stop(void)
return SBI_ENOTSUPP;
}
-static int hsm_device_hart_suspend(u32 suspend_type, ulong raddr)
+static int hsm_device_hart_suspend(u32 suspend_type)
{
if (hsm_dev && hsm_dev->hart_suspend)
- return hsm_dev->hart_suspend(suspend_type, raddr);
+ return hsm_dev->hart_suspend(suspend_type);
return SBI_ENOTSUPP;
}
@@ -319,7 +319,7 @@ int sbi_hsm_hart_stop(struct sbi_scratch *scratch, bool exitnow)
return 0;
}
-static int __sbi_hsm_suspend_ret_default(struct sbi_scratch *scratch)
+static int __sbi_hsm_suspend_default(struct sbi_scratch *scratch)
{
/* Wait for interrupt */
wfi();
@@ -359,23 +359,6 @@ static void __sbi_hsm_suspend_non_ret_restore(struct sbi_scratch *scratch)
csr_write(CSR_MIP, (hdata->saved_mip & (MIP_SSIP | MIP_STIP)));
}
-static int __sbi_hsm_suspend_non_ret_default(struct sbi_scratch *scratch,
- ulong raddr)
-{
- void (*jump_warmboot)(void) = (void (*)(void))scratch->warmboot_addr;
-
- /* Wait for interrupt */
- wfi();
-
- /*
- * Directly jump to warm reboot to simulate resume from a
- * non-retentive suspend.
- */
- jump_warmboot();
-
- return 0;
-}
-
void sbi_hsm_hart_resume_start(struct sbi_scratch *scratch)
{
int oldstate;
@@ -473,17 +456,28 @@ int sbi_hsm_hart_suspend(struct sbi_scratch *scratch, u32 suspend_type,
__sbi_hsm_suspend_non_ret_save(scratch);
/* Try platform specific suspend */
- ret = hsm_device_hart_suspend(suspend_type, scratch->warmboot_addr);
+ ret = hsm_device_hart_suspend(suspend_type);
if (ret == SBI_ENOTSUPP) {
/* Try generic implementation of default suspend types */
- if (suspend_type == SBI_HSM_SUSPEND_RET_DEFAULT) {
- ret = __sbi_hsm_suspend_ret_default(scratch);
- } else if (suspend_type == SBI_HSM_SUSPEND_NON_RET_DEFAULT) {
- ret = __sbi_hsm_suspend_non_ret_default(scratch,
- scratch->warmboot_addr);
+ if (suspend_type == SBI_HSM_SUSPEND_RET_DEFAULT ||
+ suspend_type == SBI_HSM_SUSPEND_NON_RET_DEFAULT) {
+ ret = __sbi_hsm_suspend_default(scratch);
}
}
+ /*
+ * The platform may have coordinated a retentive suspend, or it may
+ * have exited early from a non-retentive suspend. Either way, the
+ * caller is not expecting a successful return, so jump to the warm
+ * boot entry point to simulate resume from a non-retentive suspend.
+ */
+ if (ret == 0 && (suspend_type & SBI_HSM_SUSP_NON_RET_BIT)) {
+ void (*jump_warmboot)(void) =
+ (void (*)(void))scratch->warmboot_addr;
+
+ jump_warmboot();
+ }
+
fail_restore_state:
/*
* We might have successfully resumed from retentive suspend
The suspend code needs to know the resume address for two reasons: 1) Programming some hardware register or management firmware. Here we assume the hardware/firmware maintains its state between suspends, so it only needs to be programmed once at startup. 2) When a non-retentive suspend request ends up being retentive, due to lack of hardware support, pending interrupt, or for some other reason. However, the behavior here is not platform-dependent, and this can be handled in the generic hart suspend function. Since neither situation requires the platform-level suspend function to know the resume address, stop passing it to that function. Instead, handle the non-retentive to retentive situation generically. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Samuel Holland <samuel@sholland.org> --- Changes in v3: - Fix typo in commit message Changes in v2: - New patch for v2 include/sbi/sbi_hsm.h | 4 ++-- lib/sbi/sbi_hsm.c | 46 +++++++++++++++++++------------------------ 2 files changed, 22 insertions(+), 28 deletions(-)