ARM: OMAP2/3: PRM: fix bogus OMAP2xxx powerstate return values

On OMAP2xxx chips, the register bitfields for the
PM_PWSTCTRL_*.POWERSTATE and PM_PWSTST_*.LASTSTATEENTERED are
different than those used on OMAP3/4.  The order is reversed.  So, for
example, on OMAP2xxx, 0x0 indicates 'ON'; but on OMAP3/4, 0x0
indicates 'OFF'.  Similarly, on OMAP2xxx, 0x3 indicates 'OFF', but on
OMAP3/4, 0x3 indicates 'ON'.

To fix this, we treat the OMAP3/4 values as the powerdomain API
values, and create new low-level powerdomain functions for the
OMAP2xxx chips which translate between the OMAP2xxx values and the
OMAP3/4 values.

Without this patch, the conversion of the OMAP2xxx PM code to the
functional powerstate code results in a non-booting kernel.

Signed-off-by: Paul Walmsley <paul@pwsan.com>

1 files changed, 25 insertions, 3 deletions

diff --git a/arch/arm/mach-omap2/prm3xxx.c b/arch/arm/mach-omap2/prm3xxx.c
index db198d058584..4d43474d7455 100644
--- a/arch/arm/mach-omap2/prm3xxx.c
+++ b/arch/arm/mach-omap2/prm3xxx.c
@@ -278,6 +278,28 @@ static u32 omap3xxx_prm_read_reset_sources(void)
 
 /* Powerdomain low-level functions */
 
+static int omap3_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
+{
+        omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
+                                   (pwrst << OMAP_POWERSTATE_SHIFT),
+                                   pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
+        return 0;
+}
+
+static int omap3_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
+{
+        return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
+                                             OMAP2_PM_PWSTCTRL,
+                                             OMAP_POWERSTATE_MASK);
+}
+
+static int omap3_pwrdm_read_pwrst(struct powerdomain *pwrdm)
+{
+        return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
+                                             OMAP2_PM_PWSTST,
+                                             OMAP_POWERSTATEST_MASK);
+}
+
 /* Applicable only for OMAP3. Not supported on OMAP2 */
 static int omap3_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
 {
@@ -356,9 +378,9 @@ static int omap3_pwrdm_disable_hdwr_sar(struct powerdomain *pwrdm)
 }
 
 struct pwrdm_ops omap3_pwrdm_operations = {
-        .pwrdm_set_next_pwrst   = omap2_pwrdm_set_next_pwrst,
-        .pwrdm_read_next_pwrst  = omap2_pwrdm_read_next_pwrst,
-        .pwrdm_read_pwrst       = omap2_pwrdm_read_pwrst,
+        .pwrdm_set_next_pwrst   = omap3_pwrdm_set_next_pwrst,
+        .pwrdm_read_next_pwrst  = omap3_pwrdm_read_next_pwrst,
+        .pwrdm_read_pwrst       = omap3_pwrdm_read_pwrst,
         .pwrdm_read_prev_pwrst  = omap3_pwrdm_read_prev_pwrst,
         .pwrdm_set_logic_retst  = omap2_pwrdm_set_logic_retst,
         .pwrdm_read_logic_pwrst = omap3_pwrdm_read_logic_pwrst,