* [PATCH 1/4] ARM: OMAP2+: clockdomain: Fix OMAP4 ISS clk domain to support only SWSUP
2012-10-31 10:43 [PATCH 0/4] ARM: OMAP: more hwmod/PRCM fixes for 3.7-rc Paul Walmsley
@ 2012-10-31 10:43 ` Paul Walmsley
2012-10-31 10:43 ` [PATCH 2/4] ARM: OMAP: hwmod: wait for sysreset complete after enabling hwmod Paul Walmsley
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Paul Walmsley @ 2012-10-31 10:43 UTC (permalink / raw)
To: linux-arm-kernel
From: Miguel Vadillo <vadillo@ti.com>
Since CAM domain (ISS) has no module wake-up dependency
with any other clock domain of the device and the dynamic
dependency from L3_main_2 is always disabled, the domain
needs to be in force wakeup in order to be able to access
it for configure (sysconfig) it or use it.
Also since there is no clock in the domain managed automatically
by the hardware, there is no use to configure automatic
clock domain transition. SW should keep the SW_WKUP domain
transition as long as a module in the domain is required to
be functional.
Signed-off-by: Miguel Vadillo <vadillo@ti.com>
Signed-off-by: Benoit Cousson <b-cousson@ti.com>
---
arch/arm/mach-omap2/clockdomains44xx_data.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/mach-omap2/clockdomains44xx_data.c b/arch/arm/mach-omap2/clockdomains44xx_data.c
index b56d06b..95192a0 100644
--- a/arch/arm/mach-omap2/clockdomains44xx_data.c
+++ b/arch/arm/mach-omap2/clockdomains44xx_data.c
@@ -359,7 +359,7 @@ static struct clockdomain iss_44xx_clkdm = {
.clkdm_offs = OMAP4430_CM2_CAM_CAM_CDOFFS,
.wkdep_srcs = iss_wkup_sleep_deps,
.sleepdep_srcs = iss_wkup_sleep_deps,
- .flags = CLKDM_CAN_HWSUP_SWSUP,
+ .flags = CLKDM_CAN_SWSUP,
};
static struct clockdomain l3_dss_44xx_clkdm = {
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 2/4] ARM: OMAP: hwmod: wait for sysreset complete after enabling hwmod
2012-10-31 10:43 [PATCH 0/4] ARM: OMAP: more hwmod/PRCM fixes for 3.7-rc Paul Walmsley
2012-10-31 10:43 ` [PATCH 1/4] ARM: OMAP2+: clockdomain: Fix OMAP4 ISS clk domain to support only SWSUP Paul Walmsley
@ 2012-10-31 10:43 ` Paul Walmsley
2012-11-01 2:46 ` Paul Walmsley
2012-10-31 10:43 ` [PATCH 3/4] ARM: OMAP2+: hwmod: add flag to prevent hwmod code from touching IP block during init Paul Walmsley
2012-10-31 10:43 ` [PATCH 4/4] ARM: OMAP4: hwmod data: do not enable or reset the McPDM during kernel init Paul Walmsley
3 siblings, 1 reply; 6+ messages in thread
From: Paul Walmsley @ 2012-10-31 10:43 UTC (permalink / raw)
To: linux-arm-kernel
From: Tero Kristo <t-kristo@ti.com>
When waking up from off-mode, some IP blocks are reset automatically by
hardware. For this reason, software must wait until the reset has
completed before attempting to access the IP block.
This patch fixes for example the bug introduced by commit
6c31b2150ff96755d24e0ab6d6fea08a7bf5c44c ("mmc: omap_hsmmc: remove access
to SYSCONFIG register"), in which the MMC IP block is reset during
off-mode entry, but the code expects the module to be already available
during the execution of context restore.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Venkatraman S <svenkatr@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
[paul at pwsan.com: moved softreset wait code into separate function; call
from top of _enable_sysc() rather than the bottom]
Signed-off-by: Paul Walmsley <paul@pwsan.com>
---
arch/arm/mach-omap2/omap_hwmod.c | 56 +++++++++++++++++++++++++++++---------
1 file changed, 42 insertions(+), 14 deletions(-)
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index b969ab1..f9d8b2a 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -422,6 +422,38 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v)
}
/**
+ * _wait_softreset_complete - wait for an OCP softreset to complete
+ * @oh: struct omap_hwmod * to wait on
+ *
+ * Wait until the IP block represented by @oh reports that its OCP
+ * softreset is complete. This can be triggered by software (see
+ * _ocp_softreset()) or by hardware upon returning from off-mode (one
+ * example is HSMMC). Waits for up to MAX_MODULE_SOFTRESET_WAIT
+ * microseconds. Returns the number of microseconds waited.
+ */
+static int _wait_softreset_complete(struct omap_hwmod *oh)
+{
+ struct omap_hwmod_class_sysconfig *sysc;
+ u32 softrst_mask;
+ int c = 0;
+
+ sysc = oh->class->sysc;
+
+ if (sysc->sysc_flags & SYSS_HAS_RESET_STATUS)
+ omap_test_timeout((omap_hwmod_read(oh, sysc->syss_offs)
+ & SYSS_RESETDONE_MASK),
+ MAX_MODULE_SOFTRESET_WAIT, c);
+ else if (sysc->sysc_flags & SYSC_HAS_RESET_STATUS) {
+ softrst_mask = (0x1 << sysc->sysc_fields->srst_shift);
+ omap_test_timeout(!(omap_hwmod_read(oh, sysc->sysc_offs)
+ & softrst_mask),
+ MAX_MODULE_SOFTRESET_WAIT, c);
+ }
+
+ return c;
+}
+
+/**
* _set_dmadisable: set OCP_SYSCONFIG.DMADISABLE bit in @v
* @oh: struct omap_hwmod *
*
@@ -1282,6 +1314,14 @@ static void _enable_sysc(struct omap_hwmod *oh)
if (!oh->class->sysc)
return;
+ /*
+ * Wait until reset has completed, this is needed as the IP
+ * block is reset automatically by hardware in some cases
+ * (off-mode for example), and the drivers require the
+ * IP to be ready when they access it
+ */
+ _wait_softreset_complete(oh);
+
v = oh->_sysc_cache;
sf = oh->class->sysc->sysc_flags;
@@ -1804,7 +1844,7 @@ static int _am33xx_disable_module(struct omap_hwmod *oh)
*/
static int _ocp_softreset(struct omap_hwmod *oh)
{
- u32 v, softrst_mask;
+ u32 v;
int c = 0;
int ret = 0;
@@ -1834,19 +1874,7 @@ static int _ocp_softreset(struct omap_hwmod *oh)
if (oh->class->sysc->srst_udelay)
udelay(oh->class->sysc->srst_udelay);
- if (oh->class->sysc->sysc_flags & SYSS_HAS_RESET_STATUS)
- omap_test_timeout((omap_hwmod_read(oh,
- oh->class->sysc->syss_offs)
- & SYSS_RESETDONE_MASK),
- MAX_MODULE_SOFTRESET_WAIT, c);
- else if (oh->class->sysc->sysc_flags & SYSC_HAS_RESET_STATUS) {
- softrst_mask = (0x1 << oh->class->sysc->sysc_fields->srst_shift);
- omap_test_timeout(!(omap_hwmod_read(oh,
- oh->class->sysc->sysc_offs)
- & softrst_mask),
- MAX_MODULE_SOFTRESET_WAIT, c);
- }
-
+ c = _wait_softreset_complete(oh);
if (c == MAX_MODULE_SOFTRESET_WAIT)
pr_warning("omap_hwmod: %s: softreset failed (waited %d usec)\n",
oh->name, MAX_MODULE_SOFTRESET_WAIT);
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 2/4] ARM: OMAP: hwmod: wait for sysreset complete after enabling hwmod
2012-10-31 10:43 ` [PATCH 2/4] ARM: OMAP: hwmod: wait for sysreset complete after enabling hwmod Paul Walmsley
@ 2012-11-01 2:46 ` Paul Walmsley
0 siblings, 0 replies; 6+ messages in thread
From: Paul Walmsley @ 2012-11-01 2:46 UTC (permalink / raw)
To: linux-arm-kernel
Here's the updated patch for this one.
- Paul
From: Tero Kristo <t-kristo@ti.com>
Date: Mon, 29 Oct 2012 22:02:13 -0600
Subject: [PATCH 1/3] ARM: OMAP: hwmod: wait for sysreset complete after
enabling hwmod
When waking up from off-mode, some IP blocks are reset automatically by
hardware. For this reason, software must wait until the reset has
completed before attempting to access the IP block.
This patch fixes for example the bug introduced by commit
6c31b2150ff96755d24e0ab6d6fea08a7bf5c44c ("mmc: omap_hsmmc: remove access
to SYSCONFIG register"), in which the MMC IP block is reset during
off-mode entry, but the code expects the module to be already available
during the execution of context restore.
This version includes a fix from Kevin Hilman <khilman@ti.com> for
GPIO problems on the 37xx EVM - thanks Kevin.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Venkatraman S <svenkatr@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
[paul at pwsan.com: moved softreset wait code into separate function; call
from top of _enable_sysc() rather than the bottom; include fix from Kevin
Hilman for GPIO sluggishness]
Signed-off-by: Paul Walmsley <paul@pwsan.com>
---
arch/arm/mach-omap2/omap_hwmod.c | 60 +++++++++++++++++++++++++++++---------
1 file changed, 46 insertions(+), 14 deletions(-)
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index b969ab1..70267d2 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -422,6 +422,38 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v)
}
/**
+ * _wait_softreset_complete - wait for an OCP softreset to complete
+ * @oh: struct omap_hwmod * to wait on
+ *
+ * Wait until the IP block represented by @oh reports that its OCP
+ * softreset is complete. This can be triggered by software (see
+ * _ocp_softreset()) or by hardware upon returning from off-mode (one
+ * example is HSMMC). Waits for up to MAX_MODULE_SOFTRESET_WAIT
+ * microseconds. Returns the number of microseconds waited.
+ */
+static int _wait_softreset_complete(struct omap_hwmod *oh)
+{
+ struct omap_hwmod_class_sysconfig *sysc;
+ u32 softrst_mask;
+ int c = 0;
+
+ sysc = oh->class->sysc;
+
+ if (sysc->sysc_flags & SYSS_HAS_RESET_STATUS)
+ omap_test_timeout((omap_hwmod_read(oh, sysc->syss_offs)
+ & SYSS_RESETDONE_MASK),
+ MAX_MODULE_SOFTRESET_WAIT, c);
+ else if (sysc->sysc_flags & SYSC_HAS_RESET_STATUS) {
+ softrst_mask = (0x1 << sysc->sysc_fields->srst_shift);
+ omap_test_timeout(!(omap_hwmod_read(oh, sysc->sysc_offs)
+ & softrst_mask),
+ MAX_MODULE_SOFTRESET_WAIT, c);
+ }
+
+ return c;
+}
+
+/**
* _set_dmadisable: set OCP_SYSCONFIG.DMADISABLE bit in @v
* @oh: struct omap_hwmod *
*
@@ -1282,6 +1314,18 @@ static void _enable_sysc(struct omap_hwmod *oh)
if (!oh->class->sysc)
return;
+ /*
+ * Wait until reset has completed, this is needed as the IP
+ * block is reset automatically by hardware in some cases
+ * (off-mode for example), and the drivers require the
+ * IP to be ready when they access it
+ */
+ if (oh->flags & HWMOD_CONTROL_OPT_CLKS_IN_RESET)
+ _enable_optional_clocks(oh);
+ _wait_softreset_complete(oh);
+ if (oh->flags & HWMOD_CONTROL_OPT_CLKS_IN_RESET)
+ _disable_optional_clocks(oh);
+
v = oh->_sysc_cache;
sf = oh->class->sysc->sysc_flags;
@@ -1804,7 +1848,7 @@ static int _am33xx_disable_module(struct omap_hwmod *oh)
*/
static int _ocp_softreset(struct omap_hwmod *oh)
{
- u32 v, softrst_mask;
+ u32 v;
int c = 0;
int ret = 0;
@@ -1834,19 +1878,7 @@ static int _ocp_softreset(struct omap_hwmod *oh)
if (oh->class->sysc->srst_udelay)
udelay(oh->class->sysc->srst_udelay);
- if (oh->class->sysc->sysc_flags & SYSS_HAS_RESET_STATUS)
- omap_test_timeout((omap_hwmod_read(oh,
- oh->class->sysc->syss_offs)
- & SYSS_RESETDONE_MASK),
- MAX_MODULE_SOFTRESET_WAIT, c);
- else if (oh->class->sysc->sysc_flags & SYSC_HAS_RESET_STATUS) {
- softrst_mask = (0x1 << oh->class->sysc->sysc_fields->srst_shift);
- omap_test_timeout(!(omap_hwmod_read(oh,
- oh->class->sysc->sysc_offs)
- & softrst_mask),
- MAX_MODULE_SOFTRESET_WAIT, c);
- }
-
+ c = _wait_softreset_complete(oh);
if (c == MAX_MODULE_SOFTRESET_WAIT)
pr_warning("omap_hwmod: %s: softreset failed (waited %d usec)\n",
oh->name, MAX_MODULE_SOFTRESET_WAIT);
--
1.7.10.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 3/4] ARM: OMAP2+: hwmod: add flag to prevent hwmod code from touching IP block during init
2012-10-31 10:43 [PATCH 0/4] ARM: OMAP: more hwmod/PRCM fixes for 3.7-rc Paul Walmsley
2012-10-31 10:43 ` [PATCH 1/4] ARM: OMAP2+: clockdomain: Fix OMAP4 ISS clk domain to support only SWSUP Paul Walmsley
2012-10-31 10:43 ` [PATCH 2/4] ARM: OMAP: hwmod: wait for sysreset complete after enabling hwmod Paul Walmsley
@ 2012-10-31 10:43 ` Paul Walmsley
2012-10-31 10:43 ` [PATCH 4/4] ARM: OMAP4: hwmod data: do not enable or reset the McPDM during kernel init Paul Walmsley
3 siblings, 0 replies; 6+ messages in thread
From: Paul Walmsley @ 2012-10-31 10:43 UTC (permalink / raw)
To: linux-arm-kernel
Add HWMOD_EXT_OPT_MAIN_CLK flag to indicate that this IP block is
dependent on an off-chip functional clock that is not guaranteed to be
present during initialization. IP blocks marked with this flag are
left in the INITIALIZED state during kernel init.
This is a workaround for a hardware problem. It should be possible to
guarantee that at least one clock source will be present and active
for any IP block's main functional clock. This ensures that the hwmod
code can enable and reset the IP block. Resetting the IP block during
kernel init prevents any bogus bootloader, ROM code, or previous OS
configuration from affecting the kernel. Hopefully a clock
multiplexer can be added on future SoCs.
N.B., at some point in the future, it should be possible to query the
clock framework for this type of information. Then this flag should
no longer be needed.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Beno?t Cousson <b-cousson@ti.com>
---
arch/arm/mach-omap2/omap_hwmod.c | 3 +++
arch/arm/plat-omap/include/plat/omap_hwmod.h | 6 ++++++
2 files changed, 9 insertions(+)
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index f9d8b2a..4529650 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2380,6 +2380,9 @@ static int __init _setup_reset(struct omap_hwmod *oh)
if (oh->_state != _HWMOD_STATE_INITIALIZED)
return -EINVAL;
+ if (oh->flags & HWMOD_EXT_OPT_MAIN_CLK)
+ return -EPERM;
+
if (oh->rst_lines_cnt == 0) {
r = _enable(oh);
if (r) {
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index b3349f7..1db0294 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -443,6 +443,11 @@ struct omap_hwmod_omap4_prcm {
* in order to complete the reset. Optional clocks will be disabled
* again after the reset.
* HWMOD_16BIT_REG: Module has 16bit registers
+ * HWMOD_EXT_OPT_MAIN_CLK: The only main functional clock source for
+ * this IP block comes from an off-chip source and is not always
+ * enabled. This prevents the hwmod code from being able to
+ * enable and reset the IP block early. XXX Eventually it should
+ * be possible to query the clock framework for this information.
*/
#define HWMOD_SWSUP_SIDLE (1 << 0)
#define HWMOD_SWSUP_MSTANDBY (1 << 1)
@@ -453,6 +458,7 @@ struct omap_hwmod_omap4_prcm {
#define HWMOD_NO_IDLEST (1 << 6)
#define HWMOD_CONTROL_OPT_CLKS_IN_RESET (1 << 7)
#define HWMOD_16BIT_REG (1 << 8)
+#define HWMOD_EXT_OPT_MAIN_CLK (1 << 9)
/*
* omap_hwmod._int_flags definitions
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 4/4] ARM: OMAP4: hwmod data: do not enable or reset the McPDM during kernel init
2012-10-31 10:43 [PATCH 0/4] ARM: OMAP: more hwmod/PRCM fixes for 3.7-rc Paul Walmsley
` (2 preceding siblings ...)
2012-10-31 10:43 ` [PATCH 3/4] ARM: OMAP2+: hwmod: add flag to prevent hwmod code from touching IP block during init Paul Walmsley
@ 2012-10-31 10:43 ` Paul Walmsley
3 siblings, 0 replies; 6+ messages in thread
From: Paul Walmsley @ 2012-10-31 10:43 UTC (permalink / raw)
To: linux-arm-kernel
Resolve this kernel boot message:
omap_hwmod: mcpdm: cannot be enabled for reset (3)
The McPDM on OMAP4 can only receive its functional clock from an
off-chip source. This source is not guaranteed to be present on the
board, and when present, it is controlled by I2C. This would
introduce a board dependency to the early hwmod code which it was not
designed to handle. Also, neither the driver for this off-chip clock
provider nor the I2C code is available early in boot when the hwmod
code is attempting to enable and reset IP blocks. This effectively
makes it impossible to enable and reset this device during hwmod init.
At its core, this patch is a workaround for an OMAP hardware problem.
It should be possible to configure the OMAP to provide any IP block's
functional clock from an on-chip source. (This is true for almost
every IP block on the chip. As far as I know, McPDM is the only
exception.) If the kernel cannot reset and configure IP blocks, it
cannot guarantee a sane SoC state. Relying on an optional off-chip
clock also creates a board dependency which is beyond the scope of the
early hwmod code.
This patch works around the issue by marking the McPDM hwmod record
with the HWMOD_EXT_OPT_MAIN_CLK flag. This prevents the hwmod
code from touching the device early during boot.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: P?ter Ujfalusi <peter.ujfalusi@ti.com>
Cc: Beno?t Cousson <b-cousson@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
index 652d028..7bddfa5 100644
--- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
@@ -2125,6 +2125,14 @@ static struct omap_hwmod omap44xx_mcpdm_hwmod = {
.name = "mcpdm",
.class = &omap44xx_mcpdm_hwmod_class,
.clkdm_name = "abe_clkdm",
+ /*
+ * It's suspected that the McPDM requires an off-chip main
+ * functional clock, controlled via I2C. This IP block is
+ * currently reset very early during boot, before I2C is
+ * available, so it doesn't seem that we have any choice in
+ * the kernel other than to avoid resetting it.
+ */
+ .flags = HWMOD_EXT_OPT_MAIN_CLK,
.mpu_irqs = omap44xx_mcpdm_irqs,
.sdma_reqs = omap44xx_mcpdm_sdma_reqs,
.main_clk = "mcpdm_fck",
^ permalink raw reply related [flat|nested] 6+ messages in thread