The e10133 workaround was broken in two places:
- The code intended to temporarily mask all interrupts in GPC_IMRx_CORE0.
While the old register values were saved, the actual masking was
missing.
- imx_udelay() expects the system counter to run at its base frequency,
but the system counter is switched to a lower frequency earlier in
psci_system_suspend(), leading to a much longer delay than intended.
Replace the call with an equivalent loop (linux-imx 5.15 does the same)
This fixes the SoC hanging forever when there was already a wakeup IRQ
pending while suspending.
Fixes: 57b620255e ("imx: mx7: add system suspend/resume support")
Signed-off-by: Matthias Schiffer <matthias.schif...@ew.tq-group.com>
---
arch/arm/mach-imx/mx7/psci-mx7.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/arch/arm/mach-imx/mx7/psci-mx7.c b/arch/arm/mach-imx/mx7/psci-mx7.c
index f32945ea37..699a2569cb 100644
--- a/arch/arm/mach-imx/mx7/psci-mx7.c
+++ b/arch/arm/mach-imx/mx7/psci-mx7.c
@@ -643,8 +643,10 @@ __secure void psci_system_suspend(u32 __always_unused
function_id,
/* disable GIC distributor */
writel(0, GIC400_ARB_BASE_ADDR + GIC_DIST_OFFSET);
- for (i = 0; i < 4; i++)
+ for (i = 0; i < 4; i++) {
gpc_mask[i] = readl(GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0 + i * 4);
+ writel(~0, GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0 + i * 4);
+ }
/*
* enable the RBC bypass counter here
@@ -668,7 +670,7 @@ __secure void psci_system_suspend(u32 __always_unused
function_id,
writel(gpc_mask[i], GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0 + i * 4);
/*
- * now delay for a short while (3usec)
+ * now delay for a short while (~3usec)
* ARM is at 1GHz at this point
* so a short loop should be enough.
* this delay is required to ensure that
@@ -677,7 +679,8 @@ __secure void psci_system_suspend(u32 __always_unused
function_id,
* or in case an interrupt arrives just
* as ARM is about to assert DSM_request.
*/
- imx_udelay(3);
+ for (i = 0; i < 2000; i++)
+ asm volatile("");
/* save resume entry and sp in CPU0 GPR registers */
asm volatile("mov %0, sp" : "=r" (val));
--
2.25.1
