[PATCH] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[PATCH] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Paul Walmsley]

The way that we detect which OMAP3 chips support I/O wakeup and
software I/O chain clock control is broken.

Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
than the AM3505/3517.  The TI81xx family of SoCs are at present
considered to be OMAP3 SoCs, but don't support I/O wakeup.  To resolve
this, convert the existing blacklist approach to an explicit,
whitelist support, in which only SoCs which are known to support I/O
wakeup are listed.  (At present, this only includes OMAP34xx,
OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)

Also, the current code incorrectly detects the presence of a
software-controllable I/O chain clock on several chips that don't
support it.  This results in writes to reserved bitfields, unnecessary
delays, and console messages on kernels running on those chips:

    http://www.spinics.net/lists/linux-omap/msg58735.html

Convert this test to a feature test with a chip-by-chip whitelist.

Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
and doing some testing to help isolate the cause.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Dave Hylands <dhylands@gmail.com>
Cc: Steve Sakoman <sakoman@gmail.com>
---
 arch/arm/mach-omap2/id.c              |    6 +++-
 arch/arm/mach-omap2/pm34xx.c          |   44 +++++++++++++++++---------------
 arch/arm/plat-omap/include/plat/cpu.h |   17 +++++++++---
 3 files changed, 40 insertions(+), 27 deletions(-)

diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index 37efb86..eb1b8e4 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -201,8 +201,12 @@ static void __init omap3_check_features(void)
 	OMAP3_CHECK_FEATURE(status, ISP);
 	if (cpu_is_omap3630())
 		omap_features |= OMAP3_HAS_192MHZ_CLK;
-	if (!cpu_is_omap3505() && !cpu_is_omap3517())
+	if (cpu_is_omap3430() || cpu_is_omap3630())
 		omap_features |= OMAP3_HAS_IO_WAKEUP;
+	if ((omap_rev() == OMAP3430_REV_ES3_1 &&
+	     omap_rev() == OMAP3430_REV_ES3_1_2) ||
+	    cpu_is_omap3630())
+		omap_features |= OMAP3_HAS_IO_CHAIN_CTRL;
 
 	omap_features |= OMAP3_HAS_SDRC;
 
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 7255d9b..a6156bd 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -99,31 +99,28 @@ static void omap3_enable_io_chain(void)
 {
 	int timeout = 0;
 
-	if (omap_rev() >= OMAP3430_REV_ES3_1) {
-		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
-				     PM_WKEN);
-		/* Do a readback to assure write has been done */
-		omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
-
-		while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
-			 OMAP3430_ST_IO_CHAIN_MASK)) {
-			timeout++;
-			if (timeout > 1000) {
-				printk(KERN_ERR "Wake up daisy chain "
-				       "activation failed.\n");
-				return;
-			}
-			omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
-					     WKUP_MOD, PM_WKEN);
+	omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
+				   PM_WKEN);
+	/* Do a readback to assure write has been done */
+	omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
+
+	while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
+		 OMAP3430_ST_IO_CHAIN_MASK)) {
+		timeout++;
+		if (timeout > 1000) {
+			printk(KERN_ERR "Wake up daisy chain "
+			       "activation failed.\n");
+			return;
 		}
+		omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
+					   WKUP_MOD, PM_WKEN);
 	}
 }
 
 static void omap3_disable_io_chain(void)
 {
-	if (omap_rev() >= OMAP3430_REV_ES3_1)
-		omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
-				       PM_WKEN);
+	omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
+				     PM_WKEN);
 }
 
 static void omap3_core_save_context(void)
@@ -376,7 +373,8 @@ void omap_sram_idle(void)
 	    (per_next_state < PWRDM_POWER_ON ||
 	     core_next_state < PWRDM_POWER_ON)) {
 		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD, PM_WKEN);
-		omap3_enable_io_chain();
+		if (omap3_has_io_chain_ctrl())
+			omap3_enable_io_chain();
 	}
 
 	/* Block console output in case it is on one of the OMAP UARTs */
@@ -475,7 +473,8 @@ console_still_active:
 	     core_next_state < PWRDM_POWER_ON)) {
 		omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
 					     PM_WKEN);
-		omap3_disable_io_chain();
+		if (omap3_has_io_chain_ctrl())
+			omap3_disable_io_chain();
 	}
 
 	pwrdm_post_transition();
@@ -870,6 +869,9 @@ static int __init omap3_pm_init(void)
 	if (!cpu_is_omap34xx())
 		return -ENODEV;
 
+	if (!omap3_has_io_chain_ctrl())
+		pr_warning("PM: no software I/O chain control; some wakeups may be lost\n");
+
 	pm_errata_configure();
 
 	/* XXX prcm_setup_regs needs to be before enabling hw
diff --git a/arch/arm/plat-omap/include/plat/cpu.h b/arch/arm/plat-omap/include/plat/cpu.h
index 67b3d75..3a280aa 100644
--- a/arch/arm/plat-omap/include/plat/cpu.h
+++ b/arch/arm/plat-omap/include/plat/cpu.h
@@ -477,6 +477,13 @@ void omap2_check_revision(void);
 
 /*
  * Runtime detection of OMAP3 features
+ *
+ * OMAP3_HAS_IO_CHAIN_CTRL: Some later members of the OMAP3 chip
+ *    family have OS-level control over the I/O chain clock.  This is
+ *    to avoid a window during which wakeups could potentially be lost
+ *    during powerdomain transitions.  If this bit is set, it
+ *    indicates that the chip does support OS-level control of this
+ *    feature.
  */
 extern u32 omap_features;
 
@@ -488,9 +495,10 @@ extern u32 omap_features;
 #define OMAP3_HAS_192MHZ_CLK		BIT(5)
 #define OMAP3_HAS_IO_WAKEUP		BIT(6)
 #define OMAP3_HAS_SDRC			BIT(7)
-#define OMAP4_HAS_MPU_1GHZ		BIT(8)
-#define OMAP4_HAS_MPU_1_2GHZ		BIT(9)
-#define OMAP4_HAS_MPU_1_5GHZ		BIT(10)
+#define OMAP3_HAS_IO_CHAIN_CTRL		BIT(8)
+#define OMAP4_HAS_MPU_1GHZ		BIT(9)
+#define OMAP4_HAS_MPU_1_2GHZ		BIT(10)
+#define OMAP4_HAS_MPU_1_5GHZ		BIT(11)
 
 
 #define OMAP3_HAS_FEATURE(feat,flag)			\
@@ -507,12 +515,11 @@ OMAP3_HAS_FEATURE(isp, ISP)
 OMAP3_HAS_FEATURE(192mhz_clk, 192MHZ_CLK)
 OMAP3_HAS_FEATURE(io_wakeup, IO_WAKEUP)
 OMAP3_HAS_FEATURE(sdrc, SDRC)
+OMAP3_HAS_FEATURE(io_chain_ctrl, IO_CHAIN_CTRL)
 
 /*
  * Runtime detection of OMAP4 features
  */
-extern u32 omap_features;
-
 #define OMAP4_HAS_FEATURE(feat, flag)			\
 static inline unsigned int omap4_has_ ##feat(void)	\
 {							\
-- 
1.7.6.3

[PATCH] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Steve Sakoman]

On Thu, Oct 6, 2011 at 12:11 PM, Paul Walmsley <paul@pwsan.com> wrote:
>
> The way that we detect which OMAP3 chips support I/O wakeup and
> software I/O chain clock control is broken.
>
> Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
> than the AM3505/3517. ?The TI81xx family of SoCs are at present
> considered to be OMAP3 SoCs, but don't support I/O wakeup. ?To resolve
> this, convert the existing blacklist approach to an explicit,
> whitelist support, in which only SoCs which are known to support I/O
> wakeup are listed. ?(At present, this only includes OMAP34xx,
> OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)
>
> Also, the current code incorrectly detects the presence of a
> software-controllable I/O chain clock on several chips that don't
> support it. ?This results in writes to reserved bitfields, unnecessary
> delays, and console messages on kernels running on those chips:
>
> ? ?http://www.spinics.net/lists/linux-omap/msg58735.html
>
> Convert this test to a feature test with a chip-by-chip whitelist.
>
> Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
> and doing some testing to help isolate the cause.

Thanks for doing this patch so quickly!

> Signed-off-by: Paul Walmsley <paul@pwsan.com>
> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Dave Hylands <dhylands@gmail.com>
> Cc: Steve Sakoman <sakoman@gmail.com>
> ---
> ?arch/arm/mach-omap2/id.c ? ? ? ? ? ? ?| ? ?6 +++-
> ?arch/arm/mach-omap2/pm34xx.c ? ? ? ? ?| ? 44 +++++++++++++++++---------------
> ?arch/arm/plat-omap/include/plat/cpu.h | ? 17 +++++++++---
> ?3 files changed, 40 insertions(+), 27 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
> index 37efb86..eb1b8e4 100644
> --- a/arch/arm/mach-omap2/id.c
> +++ b/arch/arm/mach-omap2/id.c
> @@ -201,8 +201,12 @@ static void __init omap3_check_features(void)
> ? ? ? ?OMAP3_CHECK_FEATURE(status, ISP);
> ? ? ? ?if (cpu_is_omap3630())
> ? ? ? ? ? ? ? ?omap_features |= OMAP3_HAS_192MHZ_CLK;
> - ? ? ? if (!cpu_is_omap3505() && !cpu_is_omap3517())
> + ? ? ? if (cpu_is_omap3430() || cpu_is_omap3630())
> ? ? ? ? ? ? ? ?omap_features |= OMAP3_HAS_IO_WAKEUP;
> + ? ? ? if ((omap_rev() == OMAP3430_REV_ES3_1 &&
> + ? ? ? ? ? ?omap_rev() == OMAP3430_REV_ES3_1_2) ||

Perhaps I'm confused but shouldn't it be an || instead of &&?

We're testing for ES3.1 *or* ES3.12?

Otherwise looks good.  I'll test on my old Overo COMs.

Steve

> + ? ? ? ? ? cpu_is_omap3630())
> + ? ? ? ? ? ? ? omap_features |= OMAP3_HAS_IO_CHAIN_CTRL;
>
> ? ? ? ?omap_features |= OMAP3_HAS_SDRC;
>
> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
> index 7255d9b..a6156bd 100644
> --- a/arch/arm/mach-omap2/pm34xx.c
> +++ b/arch/arm/mach-omap2/pm34xx.c
> @@ -99,31 +99,28 @@ static void omap3_enable_io_chain(void)
> ?{
> ? ? ? ?int timeout = 0;
>
> - ? ? ? if (omap_rev() >= OMAP3430_REV_ES3_1) {
> - ? ? ? ? ? ? ? omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?PM_WKEN);
> - ? ? ? ? ? ? ? /* Do a readback to assure write has been done */
> - ? ? ? ? ? ? ? omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
> -
> - ? ? ? ? ? ? ? while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> - ? ? ? ? ? ? ? ? ? ? ? ?OMAP3430_ST_IO_CHAIN_MASK)) {
> - ? ? ? ? ? ? ? ? ? ? ? timeout++;
> - ? ? ? ? ? ? ? ? ? ? ? if (timeout > 1000) {
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? printk(KERN_ERR "Wake up daisy chain "
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?"activation failed.\n");
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? return;
> - ? ? ? ? ? ? ? ? ? ? ? }
> - ? ? ? ? ? ? ? ? ? ? ? omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?WKUP_MOD, PM_WKEN);
> + ? ? ? omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?PM_WKEN);
> + ? ? ? /* Do a readback to assure write has been done */
> + ? ? ? omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
> +
> + ? ? ? while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> + ? ? ? ? ? ? ? ?OMAP3430_ST_IO_CHAIN_MASK)) {
> + ? ? ? ? ? ? ? timeout++;
> + ? ? ? ? ? ? ? if (timeout > 1000) {
> + ? ? ? ? ? ? ? ? ? ? ? printk(KERN_ERR "Wake up daisy chain "
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?"activation failed.\n");
> + ? ? ? ? ? ? ? ? ? ? ? return;
> ? ? ? ? ? ? ? ?}
> + ? ? ? ? ? ? ? omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?WKUP_MOD, PM_WKEN);
> ? ? ? ?}
> ?}
>
> ?static void omap3_disable_io_chain(void)
> ?{
> - ? ? ? if (omap_rev() >= OMAP3430_REV_ES3_1)
> - ? ? ? ? ? ? ? omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?PM_WKEN);
> + ? ? ? omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?PM_WKEN);
> ?}
>
> ?static void omap3_core_save_context(void)
> @@ -376,7 +373,8 @@ void omap_sram_idle(void)
> ? ? ? ? ? ?(per_next_state < PWRDM_POWER_ON ||
> ? ? ? ? ? ? core_next_state < PWRDM_POWER_ON)) {
> ? ? ? ? ? ? ? ?omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD, PM_WKEN);
> - ? ? ? ? ? ? ? omap3_enable_io_chain();
> + ? ? ? ? ? ? ? if (omap3_has_io_chain_ctrl())
> + ? ? ? ? ? ? ? ? ? ? ? omap3_enable_io_chain();
> ? ? ? ?}
>
> ? ? ? ?/* Block console output in case it is on one of the OMAP UARTs */
> @@ -475,7 +473,8 @@ console_still_active:
> ? ? ? ? ? ? core_next_state < PWRDM_POWER_ON)) {
> ? ? ? ? ? ? ? ?omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? PM_WKEN);
> - ? ? ? ? ? ? ? omap3_disable_io_chain();
> + ? ? ? ? ? ? ? if (omap3_has_io_chain_ctrl())
> + ? ? ? ? ? ? ? ? ? ? ? omap3_disable_io_chain();
> ? ? ? ?}
>
> ? ? ? ?pwrdm_post_transition();
> @@ -870,6 +869,9 @@ static int __init omap3_pm_init(void)
> ? ? ? ?if (!cpu_is_omap34xx())
> ? ? ? ? ? ? ? ?return -ENODEV;
>
> + ? ? ? if (!omap3_has_io_chain_ctrl())
> + ? ? ? ? ? ? ? pr_warning("PM: no software I/O chain control; some wakeups may be lost\n");
> +
> ? ? ? ?pm_errata_configure();
>
> ? ? ? ?/* XXX prcm_setup_regs needs to be before enabling hw
> diff --git a/arch/arm/plat-omap/include/plat/cpu.h b/arch/arm/plat-omap/include/plat/cpu.h
> index 67b3d75..3a280aa 100644
> --- a/arch/arm/plat-omap/include/plat/cpu.h
> +++ b/arch/arm/plat-omap/include/plat/cpu.h
> @@ -477,6 +477,13 @@ void omap2_check_revision(void);
>
> ?/*
> ?* Runtime detection of OMAP3 features
> + *
> + * OMAP3_HAS_IO_CHAIN_CTRL: Some later members of the OMAP3 chip
> + * ? ?family have OS-level control over the I/O chain clock. ?This is
> + * ? ?to avoid a window during which wakeups could potentially be lost
> + * ? ?during powerdomain transitions. ?If this bit is set, it
> + * ? ?indicates that the chip does support OS-level control of this
> + * ? ?feature.
> ?*/
> ?extern u32 omap_features;
>
> @@ -488,9 +495,10 @@ extern u32 omap_features;
> ?#define OMAP3_HAS_192MHZ_CLK ? ? ? ? ? BIT(5)
> ?#define OMAP3_HAS_IO_WAKEUP ? ? ? ? ? ?BIT(6)
> ?#define OMAP3_HAS_SDRC ? ? ? ? ? ? ? ? BIT(7)
> -#define OMAP4_HAS_MPU_1GHZ ? ? ? ? ? ? BIT(8)
> -#define OMAP4_HAS_MPU_1_2GHZ ? ? ? ? ? BIT(9)
> -#define OMAP4_HAS_MPU_1_5GHZ ? ? ? ? ? BIT(10)
> +#define OMAP3_HAS_IO_CHAIN_CTRL ? ? ? ? ? ? ? ?BIT(8)
> +#define OMAP4_HAS_MPU_1GHZ ? ? ? ? ? ? BIT(9)
> +#define OMAP4_HAS_MPU_1_2GHZ ? ? ? ? ? BIT(10)
> +#define OMAP4_HAS_MPU_1_5GHZ ? ? ? ? ? BIT(11)
>
>
> ?#define OMAP3_HAS_FEATURE(feat,flag) ? ? ? ? ? ? ? ? ? \
> @@ -507,12 +515,11 @@ OMAP3_HAS_FEATURE(isp, ISP)
> ?OMAP3_HAS_FEATURE(192mhz_clk, 192MHZ_CLK)
> ?OMAP3_HAS_FEATURE(io_wakeup, IO_WAKEUP)
> ?OMAP3_HAS_FEATURE(sdrc, SDRC)
> +OMAP3_HAS_FEATURE(io_chain_ctrl, IO_CHAIN_CTRL)
>
> ?/*
> ?* Runtime detection of OMAP4 features
> ?*/
> -extern u32 omap_features;
> -
> ?#define OMAP4_HAS_FEATURE(feat, flag) ? ? ? ? ? ? ? ? ?\
> ?static inline unsigned int omap4_has_ ##feat(void) ? ? \
> ?{ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?\
> --
> 1.7.6.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at ?http://vger.kernel.org/majordomo-info.html
>

[PATCH] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Paul Walmsley]

On Thu, 6 Oct 2011, Steve Sakoman wrote:

> Perhaps I'm confused but shouldn't it be an || instead of &&?
> 
> We're testing for ES3.1 *or* ES3.12?

You're correct - thanks for catching this.  v2 on its way.

- Paul

[PATCH v2] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Paul Walmsley]

The way that we detect which OMAP3 chips support I/O wakeup and
software I/O chain clock control is broken.

Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
than the AM3505/3517.  The TI81xx family of SoCs are at present
considered to be OMAP3 SoCs, but don't support I/O wakeup.  To resolve
this, convert the existing blacklist approach to an explicit,
whitelist support, in which only SoCs which are known to support I/O
wakeup are listed.  (At present, this only includes OMAP34xx,
OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)

Also, the current code incorrectly detects the presence of a
software-controllable I/O chain clock on several chips that don't
support it.  This results in writes to reserved bitfields, unnecessary
delays, and console messages on kernels running on those chips:

    http://www.spinics.net/lists/linux-omap/msg58735.html

Convert this test to a feature test with a chip-by-chip whitelist.

Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
and doing some testing to help isolate the cause.  Thanks to Steve
Sakoman <sakoman@gmail.com> for catching a bug in the first version of
this patch.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Dave Hylands <dhylands@gmail.com>
Cc: Steve Sakoman <sakoman@gmail.com>
---
 arch/arm/mach-omap2/id.c              |    6 +++-
 arch/arm/mach-omap2/pm34xx.c          |   44 +++++++++++++++++---------------
 arch/arm/plat-omap/include/plat/cpu.h |   17 +++++++++---
 3 files changed, 40 insertions(+), 27 deletions(-)

diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index 37efb86..707fbb1 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -201,8 +201,12 @@ static void __init omap3_check_features(void)
 	OMAP3_CHECK_FEATURE(status, ISP);
 	if (cpu_is_omap3630())
 		omap_features |= OMAP3_HAS_192MHZ_CLK;
-	if (!cpu_is_omap3505() && !cpu_is_omap3517())
+	if (cpu_is_omap3430() || cpu_is_omap3630())
 		omap_features |= OMAP3_HAS_IO_WAKEUP;
+	if ((omap_rev() == OMAP3430_REV_ES3_1 ||
+	     omap_rev() == OMAP3430_REV_ES3_1_2) ||
+	    cpu_is_omap3630())
+		omap_features |= OMAP3_HAS_IO_CHAIN_CTRL;
 
 	omap_features |= OMAP3_HAS_SDRC;
 
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 7255d9b..a6156bd 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -99,31 +99,28 @@ static void omap3_enable_io_chain(void)
 {
 	int timeout = 0;
 
-	if (omap_rev() >= OMAP3430_REV_ES3_1) {
-		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
-				     PM_WKEN);
-		/* Do a readback to assure write has been done */
-		omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
-
-		while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
-			 OMAP3430_ST_IO_CHAIN_MASK)) {
-			timeout++;
-			if (timeout > 1000) {
-				printk(KERN_ERR "Wake up daisy chain "
-				       "activation failed.\n");
-				return;
-			}
-			omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
-					     WKUP_MOD, PM_WKEN);
+	omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
+				   PM_WKEN);
+	/* Do a readback to assure write has been done */
+	omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
+
+	while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
+		 OMAP3430_ST_IO_CHAIN_MASK)) {
+		timeout++;
+		if (timeout > 1000) {
+			printk(KERN_ERR "Wake up daisy chain "
+			       "activation failed.\n");
+			return;
 		}
+		omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
+					   WKUP_MOD, PM_WKEN);
 	}
 }
 
 static void omap3_disable_io_chain(void)
 {
-	if (omap_rev() >= OMAP3430_REV_ES3_1)
-		omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
-				       PM_WKEN);
+	omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
+				     PM_WKEN);
 }
 
 static void omap3_core_save_context(void)
@@ -376,7 +373,8 @@ void omap_sram_idle(void)
 	    (per_next_state < PWRDM_POWER_ON ||
 	     core_next_state < PWRDM_POWER_ON)) {
 		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD, PM_WKEN);
-		omap3_enable_io_chain();
+		if (omap3_has_io_chain_ctrl())
+			omap3_enable_io_chain();
 	}
 
 	/* Block console output in case it is on one of the OMAP UARTs */
@@ -475,7 +473,8 @@ console_still_active:
 	     core_next_state < PWRDM_POWER_ON)) {
 		omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
 					     PM_WKEN);
-		omap3_disable_io_chain();
+		if (omap3_has_io_chain_ctrl())
+			omap3_disable_io_chain();
 	}
 
 	pwrdm_post_transition();
@@ -870,6 +869,9 @@ static int __init omap3_pm_init(void)
 	if (!cpu_is_omap34xx())
 		return -ENODEV;
 
+	if (!omap3_has_io_chain_ctrl())
+		pr_warning("PM: no software I/O chain control; some wakeups may be lost\n");
+
 	pm_errata_configure();
 
 	/* XXX prcm_setup_regs needs to be before enabling hw
diff --git a/arch/arm/plat-omap/include/plat/cpu.h b/arch/arm/plat-omap/include/plat/cpu.h
index 67b3d75..3a280aa 100644
--- a/arch/arm/plat-omap/include/plat/cpu.h
+++ b/arch/arm/plat-omap/include/plat/cpu.h
@@ -477,6 +477,13 @@ void omap2_check_revision(void);
 
 /*
  * Runtime detection of OMAP3 features
+ *
+ * OMAP3_HAS_IO_CHAIN_CTRL: Some later members of the OMAP3 chip
+ *    family have OS-level control over the I/O chain clock.  This is
+ *    to avoid a window during which wakeups could potentially be lost
+ *    during powerdomain transitions.  If this bit is set, it
+ *    indicates that the chip does support OS-level control of this
+ *    feature.
  */
 extern u32 omap_features;
 
@@ -488,9 +495,10 @@ extern u32 omap_features;
 #define OMAP3_HAS_192MHZ_CLK		BIT(5)
 #define OMAP3_HAS_IO_WAKEUP		BIT(6)
 #define OMAP3_HAS_SDRC			BIT(7)
-#define OMAP4_HAS_MPU_1GHZ		BIT(8)
-#define OMAP4_HAS_MPU_1_2GHZ		BIT(9)
-#define OMAP4_HAS_MPU_1_5GHZ		BIT(10)
+#define OMAP3_HAS_IO_CHAIN_CTRL		BIT(8)
+#define OMAP4_HAS_MPU_1GHZ		BIT(9)
+#define OMAP4_HAS_MPU_1_2GHZ		BIT(10)
+#define OMAP4_HAS_MPU_1_5GHZ		BIT(11)
 
 
 #define OMAP3_HAS_FEATURE(feat,flag)			\
@@ -507,12 +515,11 @@ OMAP3_HAS_FEATURE(isp, ISP)
 OMAP3_HAS_FEATURE(192mhz_clk, 192MHZ_CLK)
 OMAP3_HAS_FEATURE(io_wakeup, IO_WAKEUP)
 OMAP3_HAS_FEATURE(sdrc, SDRC)
+OMAP3_HAS_FEATURE(io_chain_ctrl, IO_CHAIN_CTRL)
 
 /*
  * Runtime detection of OMAP4 features
  */
-extern u32 omap_features;
-
 #define OMAP4_HAS_FEATURE(feat, flag)			\
 static inline unsigned int omap4_has_ ##feat(void)	\
 {							\
-- 
1.7.6.3

[PATCH v2] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Steve Sakoman]

On Thu, Oct 6, 2011 at 12:47 PM, Paul Walmsley <paul@pwsan.com> wrote:
>
> The way that we detect which OMAP3 chips support I/O wakeup and
> software I/O chain clock control is broken.
>
> Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
> than the AM3505/3517. ?The TI81xx family of SoCs are at present
> considered to be OMAP3 SoCs, but don't support I/O wakeup. ?To resolve
> this, convert the existing blacklist approach to an explicit,
> whitelist support, in which only SoCs which are known to support I/O
> wakeup are listed. ?(At present, this only includes OMAP34xx,
> OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)
>
> Also, the current code incorrectly detects the presence of a
> software-controllable I/O chain clock on several chips that don't
> support it. ?This results in writes to reserved bitfields, unnecessary
> delays, and console messages on kernels running on those chips:
>
> ? ?http://www.spinics.net/lists/linux-omap/msg58735.html
>
> Convert this test to a feature test with a chip-by-chip whitelist.
>
> Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
> and doing some testing to help isolate the cause. ?Thanks to Steve
> Sakoman <sakoman@gmail.com> for catching a bug in the first version of
> this patch.
>
> Signed-off-by: Paul Walmsley <paul@pwsan.com>
> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Dave Hylands <dhylands@gmail.com>
> Cc: Steve Sakoman <sakoman@gmail.com>

I just tested a Linux 3.0 version of the patch on both ES2.1
and ES3.1 and it works just fine.

So here is my:

Tested-by: Steve Sakoman <steve@sakoman.com>

[PATCH v3] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Paul Walmsley]

[PATCH v3] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Kevin Hilman]

Paul Walmsley <paul@pwsan.com> writes:

> The way that we detect which OMAP3 chips support I/O wakeup and
> software I/O chain clock control is broken.
>
> Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
> than the AM3505/3517.  The TI81xx family of SoCs are at present
> considered to be OMAP3 SoCs, but don't support I/O wakeup.  To resolve
> this, convert the existing blacklist approach to an explicit,
> whitelist support, in which only SoCs which are known to support I/O
> wakeup are listed.  (At present, this only includes OMAP34xx,
> OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)
>
> Also, the current code incorrectly detects the presence of a
> software-controllable I/O chain clock on several chips that don't
> support it.  This results in writes to reserved bitfields, unnecessary
> delays, and console messages on kernels running on those chips:
>
>     http://www.spinics.net/lists/linux-omap/msg58735.html
>
> Convert this test to a feature test with a chip-by-chip whitelist.
>
> Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
> and doing some testing to help isolate the cause.  Thanks to Steve
> Sakoman <sakoman@gmail.com> for catching a bug in the first version of
> this patch.

Based on the comments from Russell, I made a couple minor changes.
Here's the updated version (also in my for_3.1/pm-fixes-3 branch.)

Other than that, it looks like a good cleanup, queueing for v3.2 and
will submit to stable as well.

Tony, do you think we can still queue this as a fix for v3.1?

Kevin

[PATCH v2] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Russell King - ARM Linux]

On Thu, Oct 06, 2011 at 01:47:22PM -0600, Paul Walmsley wrote:
> +	if ((omap_rev() == OMAP3430_REV_ES3_1 ||
> +	     omap_rev() == OMAP3430_REV_ES3_1_2) ||
> +	    cpu_is_omap3630())
> +		omap_features |= OMAP3_HAS_IO_CHAIN_CTRL;

	(a || b) || c === a || b || c

IOW, no need for the additional parens.

> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
> index 7255d9b..a6156bd 100644
> --- a/arch/arm/mach-omap2/pm34xx.c
> +++ b/arch/arm/mach-omap2/pm34xx.c
> @@ -99,31 +99,28 @@ static void omap3_enable_io_chain(void)
>  {
>  	int timeout = 0;
>  
> -	if (omap_rev() >= OMAP3430_REV_ES3_1) {
> -		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> -				     PM_WKEN);
> -		/* Do a readback to assure write has been done */
> -		omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
> -
> -		while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> -			 OMAP3430_ST_IO_CHAIN_MASK)) {
> -			timeout++;
> -			if (timeout > 1000) {
> -				printk(KERN_ERR "Wake up daisy chain "
> -				       "activation failed.\n");
> -				return;
> -			}
> -			omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> -					     WKUP_MOD, PM_WKEN);
> +	omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> +				   PM_WKEN);
> +	/* Do a readback to assure write has been done */
> +	omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
> +
> +	while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> +		 OMAP3430_ST_IO_CHAIN_MASK)) {
> +		timeout++;
> +		if (timeout > 1000) {
> +			printk(KERN_ERR "Wake up daisy chain "
> +			       "activation failed.\n");
> +			return;
>  		}
> +		omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> +					   WKUP_MOD, PM_WKEN);
>  	}

This should've been caught before.  Two things:

1. Do you know how long it takes this to time out?
2. Don't wrap error printks, it prevents them being grepped for.

[PATCH v2] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Paul Walmsley]

On Thu, 6 Oct 2011, Russell King - ARM Linux wrote:

> On Thu, Oct 06, 2011 at 01:47:22PM -0600, Paul Walmsley wrote:
> > +	if ((omap_rev() == OMAP3430_REV_ES3_1 ||
> > +	     omap_rev() == OMAP3430_REV_ES3_1_2) ||
> > +	    cpu_is_omap3630())
> > +		omap_features |= OMAP3_HAS_IO_CHAIN_CTRL;
> 
> 	(a || b) || c === a || b || c
> 
> IOW, no need for the additional parens.

Thanks; patch updated.

> > diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
> > index 7255d9b..a6156bd 100644
> > --- a/arch/arm/mach-omap2/pm34xx.c
> > +++ b/arch/arm/mach-omap2/pm34xx.c
> > @@ -99,31 +99,28 @@ static void omap3_enable_io_chain(void)
> >  {
> >  	int timeout = 0;
> >  
> > -	if (omap_rev() >= OMAP3430_REV_ES3_1) {
> > -		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> > -				     PM_WKEN);
> > -		/* Do a readback to assure write has been done */
> > -		omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
> > -
> > -		while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> > -			 OMAP3430_ST_IO_CHAIN_MASK)) {
> > -			timeout++;
> > -			if (timeout > 1000) {
> > -				printk(KERN_ERR "Wake up daisy chain "
> > -				       "activation failed.\n");
> > -				return;
> > -			}
> > -			omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> > -					     WKUP_MOD, PM_WKEN);
> > +	omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
> > +				   PM_WKEN);
> > +	/* Do a readback to assure write has been done */
> > +	omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
> > +
> > +	while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> > +		 OMAP3430_ST_IO_CHAIN_MASK)) {
> > +		timeout++;
> > +		if (timeout > 1000) {
> > +			printk(KERN_ERR "Wake up daisy chain "
> > +			       "activation failed.\n");
> > +			return;
> >  		}
> > +		omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> > +					   WKUP_MOD, PM_WKEN);
> >  	}
> 
> This should've been caught before.  Two things:
> 
> 1. Do you know how long it takes this to time out?

No, I don't; and I doubt the original author did either.

Really there should be at least a udelay(1) in that code; since as it 
stands right now, there's at least a partial CPU/interconnect/high 
frequency oscillator speed dependency in that loop.

But this patch was intended to be a minimal fix, avoiding code changes 
that are unrelated to the I/O chain feature detection change.  Those lines 
just showed up due to the indentation level change...
 
> 2. Don't wrap error printks, it prevents them being grepped for.

Thanks; patch updated.


- Paul

[PATCH v3] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Paul Walmsley]

The way that we detect which OMAP3 chips support I/O wakeup and
software I/O chain clock control is broken.

Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
than the AM3505/3517.  The TI81xx family of SoCs are at present
considered to be OMAP3 SoCs, but don't support I/O wakeup.  To resolve
this, convert the existing blacklist approach to an explicit,
whitelist support, in which only SoCs which are known to support I/O
wakeup are listed.  (At present, this only includes OMAP34xx,
OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)

Also, the current code incorrectly detects the presence of a
software-controllable I/O chain clock on several chips that don't
support it.  This results in writes to reserved bitfields, unnecessary
delays, and console messages on kernels running on those chips:

    http://www.spinics.net/lists/linux-omap/msg58735.html

Convert this test to a feature test with a chip-by-chip whitelist.

Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
and doing some testing to help isolate the cause.  Thanks to Steve
Sakoman <sakoman@gmail.com> for catching a bug in the first version of
this patch.  Thanks to Russell King <linux@arm.linux.org.uk> for
comments.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Dave Hylands <dhylands@gmail.com>
Cc: Steve Sakoman <sakoman@gmail.com>
Tested-by: Steve Sakoman <sakoman@gmail.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
---

This version incorporates some comments from RMK - an unnecessary 
set of parentheses are removed and a two-part error message string is 
joined.  Also, the printk(KERN_ERR has been converted into a pr_err(. 

 arch/arm/mach-omap2/id.c              |    5 +++-
 arch/arm/mach-omap2/pm34xx.c          |   43 +++++++++++++++++----------------
 arch/arm/plat-omap/include/plat/cpu.h |   17 +++++++++----
 3 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index 37efb86..a1ccb66 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -201,8 +201,11 @@ static void __init omap3_check_features(void)
 	OMAP3_CHECK_FEATURE(status, ISP);
 	if (cpu_is_omap3630())
 		omap_features |= OMAP3_HAS_192MHZ_CLK;
-	if (!cpu_is_omap3505() && !cpu_is_omap3517())
+	if (cpu_is_omap3430() || cpu_is_omap3630())
 		omap_features |= OMAP3_HAS_IO_WAKEUP;
+	if (cpu_is_omap3630() || omap_rev() == OMAP3430_REV_ES3_1 ||
+	    omap_rev() == OMAP3430_REV_ES3_1_2)
+		omap_features |= OMAP3_HAS_IO_CHAIN_CTRL;
 
 	omap_features |= OMAP3_HAS_SDRC;
 
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 7255d9b..979ed39 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -99,31 +99,27 @@ static void omap3_enable_io_chain(void)
 {
 	int timeout = 0;
 
-	if (omap_rev() >= OMAP3430_REV_ES3_1) {
-		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
-				     PM_WKEN);
-		/* Do a readback to assure write has been done */
-		omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
-
-		while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
-			 OMAP3430_ST_IO_CHAIN_MASK)) {
-			timeout++;
-			if (timeout > 1000) {
-				printk(KERN_ERR "Wake up daisy chain "
-				       "activation failed.\n");
-				return;
-			}
-			omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
-					     WKUP_MOD, PM_WKEN);
+	omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
+				   PM_WKEN);
+	/* Do a readback to assure write has been done */
+	omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
+
+	while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
+		 OMAP3430_ST_IO_CHAIN_MASK)) {
+		timeout++;
+		if (timeout > 1000) {
+			pr_err("Wake up daisy chain activation failed.\n");
+			return;
 		}
+		omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
+					   WKUP_MOD, PM_WKEN);
 	}
 }
 
 static void omap3_disable_io_chain(void)
 {
-	if (omap_rev() >= OMAP3430_REV_ES3_1)
-		omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
-				       PM_WKEN);
+	omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
+				     PM_WKEN);
 }
 
 static void omap3_core_save_context(void)
@@ -376,7 +372,8 @@ void omap_sram_idle(void)
 	    (per_next_state < PWRDM_POWER_ON ||
 	     core_next_state < PWRDM_POWER_ON)) {
 		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD, PM_WKEN);
-		omap3_enable_io_chain();
+		if (omap3_has_io_chain_ctrl())
+			omap3_enable_io_chain();
 	}
 
 	/* Block console output in case it is on one of the OMAP UARTs */
@@ -475,7 +472,8 @@ console_still_active:
 	     core_next_state < PWRDM_POWER_ON)) {
 		omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
 					     PM_WKEN);
-		omap3_disable_io_chain();
+		if (omap3_has_io_chain_ctrl())
+			omap3_disable_io_chain();
 	}
 
 	pwrdm_post_transition();
@@ -870,6 +868,9 @@ static int __init omap3_pm_init(void)
 	if (!cpu_is_omap34xx())
 		return -ENODEV;
 
+	if (!omap3_has_io_chain_ctrl())
+		pr_warning("PM: no software I/O chain control; some wakeups may be lost\n");
+
 	pm_errata_configure();
 
 	/* XXX prcm_setup_regs needs to be before enabling hw
diff --git a/arch/arm/plat-omap/include/plat/cpu.h b/arch/arm/plat-omap/include/plat/cpu.h
index 67b3d75..3a280aa 100644
--- a/arch/arm/plat-omap/include/plat/cpu.h
+++ b/arch/arm/plat-omap/include/plat/cpu.h
@@ -477,6 +477,13 @@ void omap2_check_revision(void);
 
 /*
  * Runtime detection of OMAP3 features
+ *
+ * OMAP3_HAS_IO_CHAIN_CTRL: Some later members of the OMAP3 chip
+ *    family have OS-level control over the I/O chain clock.  This is
+ *    to avoid a window during which wakeups could potentially be lost
+ *    during powerdomain transitions.  If this bit is set, it
+ *    indicates that the chip does support OS-level control of this
+ *    feature.
  */
 extern u32 omap_features;
 
@@ -488,9 +495,10 @@ extern u32 omap_features;
 #define OMAP3_HAS_192MHZ_CLK		BIT(5)
 #define OMAP3_HAS_IO_WAKEUP		BIT(6)
 #define OMAP3_HAS_SDRC			BIT(7)
-#define OMAP4_HAS_MPU_1GHZ		BIT(8)
-#define OMAP4_HAS_MPU_1_2GHZ		BIT(9)
-#define OMAP4_HAS_MPU_1_5GHZ		BIT(10)
+#define OMAP3_HAS_IO_CHAIN_CTRL		BIT(8)
+#define OMAP4_HAS_MPU_1GHZ		BIT(9)
+#define OMAP4_HAS_MPU_1_2GHZ		BIT(10)
+#define OMAP4_HAS_MPU_1_5GHZ		BIT(11)
 
 
 #define OMAP3_HAS_FEATURE(feat,flag)			\
@@ -507,12 +515,11 @@ OMAP3_HAS_FEATURE(isp, ISP)
 OMAP3_HAS_FEATURE(192mhz_clk, 192MHZ_CLK)
 OMAP3_HAS_FEATURE(io_wakeup, IO_WAKEUP)
 OMAP3_HAS_FEATURE(sdrc, SDRC)
+OMAP3_HAS_FEATURE(io_chain_ctrl, IO_CHAIN_CTRL)
 
 /*
  * Runtime detection of OMAP4 features
  */
-extern u32 omap_features;
-
 #define OMAP4_HAS_FEATURE(feat, flag)			\
 static inline unsigned int omap4_has_ ##feat(void)	\
 {							\
-- 
1.7.6.3

[PATCH v3] ARM: OMAP3: PM: fix I/O wakeup and I/O chain clock control detection

[Kevin Hilman]

Paul Walmsley <paul@pwsan.com> writes:

> The way that we detect which OMAP3 chips support I/O wakeup and
> software I/O chain clock control is broken.
>
> Currently, I/O wakeup is marked as present for all OMAP3 SoCs other
> than the AM3505/3517.  The TI81xx family of SoCs are at present
> considered to be OMAP3 SoCs, but don't support I/O wakeup.  To resolve
> this, convert the existing blacklist approach to an explicit,
> whitelist support, in which only SoCs which are known to support I/O
> wakeup are listed.  (At present, this only includes OMAP34xx,
> OMAP3503, OMAP3515, OMAP3525, OMAP3530, and OMAP36xx.)
>
> Also, the current code incorrectly detects the presence of a
> software-controllable I/O chain clock on several chips that don't
> support it.  This results in writes to reserved bitfields, unnecessary
> delays, and console messages on kernels running on those chips:
>
>     http://www.spinics.net/lists/linux-omap/msg58735.html
>
> Convert this test to a feature test with a chip-by-chip whitelist.
>
> Thanks to Dave Hylands <dhylands@gmail.com> for reporting this problem
> and doing some testing to help isolate the cause.  Thanks to Steve
> Sakoman <sakoman@gmail.com> for catching a bug in the first version of
> this patch.  Thanks to Russell King <linux@arm.linux.org.uk> for
> comments.
>
> Signed-off-by: Paul Walmsley <paul@pwsan.com>
> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Dave Hylands <dhylands@gmail.com>
> Cc: Steve Sakoman <sakoman@gmail.com>
> Tested-by: Steve Sakoman <sakoman@gmail.com>
> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
> ---
>
> This version incorporates some comments from RMK - an unnecessary 
> set of parentheses are removed and a two-part error message string is 
> joined.  Also, the printk(KERN_ERR has been converted into a pr_err(. 

OK, looks like we made some parallel changes.

Dropping my version and will queue this one (branch: for_3.2/pm-cleanup-2)

Kevin