[PATCH 06/12] ARM: OMAP44xx: PM: convert to use the functional power states API
From: Tero Kristo <hidden>
Date: 2013-01-04 14:01:24
Also in:
linux-omap
Subsystem:
arm port, omap power management support, omap2+ support, the rest · Maintainers:
Russell King, Kevin Hilman, Aaro Koskinen, Andreas Kemnade, Kevin Hilman, Roger Quadros, Tony Lindgren, Linus Torvalds
Hi Paul, On Sun, 2012-12-09 at 10:53 -0700, Paul Walmsley wrote: <clip>
quoted hunk ↗ jump to hunk
@@ -40,20 +39,19 @@ static LIST_HEAD(pwrst_list); static int omap4_pm_suspend(void) { struct power_state *pwrst; - int state, ret = 0; + int prev_fpwrst; + int ret = 0; u32 cpu_id = smp_processor_id(); + /* XXX Seems like these two loops could be combined into one loop? */ +
They can be combined yes. <clip>
quoted hunk ↗ jump to hunk
@@ -113,10 +113,10 @@ static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused) return -ENOMEM; pwrst->pwrdm = pwrdm; - pwrst->next_state = PWRDM_POWER_RET; + pwrst->next_fpwrst = PWRDM_FUNC_PWRST_CSWR; list_add(&pwrst->node, &pwrst_list); - return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state); + return WARN_ON(pwrdm_set_fpwrst(pwrst->pwrdm, pwrst->next_fpwrst));
This causes a regression on omap4, as several power domains can't idle after this anymore (they get programmed to ON state due to CSWR not being supported on them.) Following patch fixes this problem (applies on top of the whole set): ============= From: Tero Kristo <redacted> Date: Wed, 2 Jan 2013 18:05:42 +0200 Subject: [PATCH] ARM: OMAP4: PM: fix the power state setup After the functional power state code changes, OMAP4 PM init code programs powerdomains now to ON state if the domain does not support CSWR. This breaks suspend and should be avoided. Fixed by adding a loop to the pwrdms_setup code, that for each domain selects the next fpwrst based on following order: CSWR, OSWR, OFF, ON. This allows all the domains to enter supported low power states, instead of always selecting ON. Signed-off-by: Tero Kristo <redacted> --- arch/arm/mach-omap2/pm44xx.c | 22 +++++++++++++++++----- 1 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
index 8775ee5..67f05fe 100644
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c@@ -88,6 +88,13 @@ static int omap4_pm_suspend(void) static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused) { struct power_state *pwrst; + const u8 fpwrst_states[] = { + PWRDM_FUNC_PWRST_CSWR, + PWRDM_FUNC_PWRST_OSWR, + PWRDM_FUNC_PWRST_OFF, + PWRDM_FUNC_PWRST_ON, + }; + int i; if (!pwrdm->pwrsts) return 0;
@@ -106,12 +113,17 @@ static int __init pwrdms_setup(struct powerdomain*pwrdm, void *unused)
pwrst->pwrdm = pwrdm;
/*
- * XXX This should be replaced by explicit lists of
- * powerdomains with specific powerstates to set
+ * We attempt to program the fpwrst of a domain in the following
+ * order: CSWR, OSWR, OFF, ON. This is needed as some domains
+ * don't support retention, and instead should go to off in low
+ * power modes. If everything else fails, the code falls back
+ * to ON state.
*/
- pwrst->next_fpwrst = PWRDM_FUNC_PWRST_CSWR;
- if (!pwrdm_supports_fpwrst(pwrdm, pwrst->next_fpwrst))
- pwrst->next_fpwrst = PWRDM_FUNC_PWRST_ON;
+ for (i = 0; i < ARRAY_SIZE(fpwrst_states); i++) {
+ pwrst->next_fpwrst = fpwrst_states[i];
+ if (pwrdm_supports_fpwrst(pwrdm, pwrst->next_fpwrst))
+ break;
+ }
list_add(&pwrst->node, &pwrst_list);
return WARN_ON(pwrdm_set_fpwrst(pwrst->pwrdm, pwrst->next_fpwrst));
--
1.7.4.1