platform/x86: pmc_atom: Check state of PMC clocks on s2idle

Extend the s2idle check with checking that none of the PMC clocks
is in the forced-on state. If one of the clocks is in forced on
state then S0i3 cannot be reached.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20240305105915.76242-5-hdegoede@redhat.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/pmc_atom.c b/drivers/platform/x86/pmc_atom.c
index 7d391bd36eae3eb759763393fe33943a963d82a7..0aa7076bc9cc7f5974a73620075e299f8919653a 100644 (file)
--- a/drivers/platform/x86/pmc_atom.c
+++ b/drivers/platform/x86/pmc_atom.c
@@ -477,6 +477,7 @@ static void pmc_s2idle_check(void)
        u32 func_dis, func_dis_2;
        u32 d3_sts_0, d3_sts_1;
        u32 false_pos_sts_0, false_pos_sts_1;
+       int i;
 
        func_dis = pmc_reg_read(pmc, PMC_FUNC_DIS);
        func_dis_2 = pmc_reg_read(pmc, PMC_FUNC_DIS_2);
@@ -501,6 +502,16 @@ static void pmc_s2idle_check(void)
 
        pmc_dev_state_check(d3_sts_0, m->d3_sts_0, func_dis, m->func_dis, false_pos_sts_0);
        pmc_dev_state_check(d3_sts_1, m->d3_sts_1, func_dis_2, m->func_dis_2, false_pos_sts_1);
+
+       /* Forced-on PMC clocks prevent S0i3 */
+       for (i = 0; i < PMC_CLK_NUM; i++) {
+               u32 ctl = pmc_reg_read(pmc, PMC_CLK_CTL_OFFSET + 4 * i);
+
+               if ((ctl & PMC_MASK_CLK_CTL) != PMC_CLK_CTL_FORCE_ON)
+                       continue;
+
+               pr_err("clock %d is ON prior to freeze (ctl 0x%08x)\n", i, ctl);
+       }
 }
 
 static struct acpi_s2idle_dev_ops pmc_s2idle_ops = {