[PATCH] OMAP2+: hwmod: use status bit info for reset line

Omar Ramirez Luna omar.ramirez at ti.com
Tue Mar 1 19:46:49 EST 2011


On OMAP2 and OMAP3 the reset ctrl shift doesn't match the
status bit, as it does on OMAP4, when handling the reset lines.

This patch adds a new member in the reset info structure, so now it
can be added as part of hwmod data, and checked accordingly for
OMAP2 or 3; otherwise, there could be cases when the shift masks
doesn't match both of the registers, and a successful reset might
throw an error message or vice versa.

Signed-off-by: Omar Ramirez Luna <omar.ramirez at ti.com>
---

In OMAP3 (with an IVA), this affects IVA domain (in parenthesis the
shift needed).

RSTCTRL has:
  RST3(2)
  RST2(1)
  RST1(0)

RSTST has:
...
IVA2_SW_RST3 (10)
IVA2_SW_RST2 (9)
IVA2_SW_RST1 (8)
COREDOMAINWKUP_RST (3)
GLOBALWARM_RST (2)
DOMAINWKUP_RST (1)
GLOBALCOLD_RST (0)

In OMAP2, it could potentially affect GFX, DSP and MDM domains; if the
resets are also used.

 arch/arm/mach-omap2/omap_hwmod.c             |   64 ++++++++++++++------------
 arch/arm/mach-omap2/prm2xxx_3xxx.c           |   18 ++++---
 arch/arm/mach-omap2/prm2xxx_3xxx.h           |    5 +-
 arch/arm/plat-omap/include/plat/omap_hwmod.h |    2 +
 4 files changed, 50 insertions(+), 39 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index e282e35..019fb29 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -972,25 +972,29 @@ static int _wait_target_ready(struct omap_hwmod *oh)
 }
 
 /**
- * _lookup_hardreset - return the register bit shift for this hwmod/reset line
+ * _lookup_hardreset - fill register bit info for this hwmod/reset line
  * @oh: struct omap_hwmod *
  * @name: name of the reset line in the context of this hwmod
+ * @r: pointer to be filled with the register bit shifts
  *
  * Return the bit position of the reset line that match the
  * input name. Return -ENOENT if not found.
  */
-static u8 _lookup_hardreset(struct omap_hwmod *oh, const char *name)
+static u8 _lookup_hardreset(struct omap_hwmod *oh, const char *name,
+			    struct omap_hwmod_rst_info *r)
 {
 	int i;
 
 	for (i = 0; i < oh->rst_lines_cnt; i++) {
 		const char *rst_line = oh->rst_lines[i].name;
 		if (!strcmp(rst_line, name)) {
-			u8 shift = oh->rst_lines[i].rst_shift;
-			pr_debug("omap_hwmod: %s: _lookup_hardreset: %s: %d\n",
-				 oh->name, rst_line, shift);
+			r->rst_shift = oh->rst_lines[i].rst_shift;
+			r->st_shift = oh->rst_lines[i].st_shift;
+			pr_debug("omap_hwmod: %s: %s: %s: rst %d st %d\n",
+				 oh->name, __func__, rst_line, r->rst_shift,
+				 r->st_shift);
 
-			return shift;
+			return 0;
 		}
 	}
 
@@ -1009,21 +1013,22 @@ static u8 _lookup_hardreset(struct omap_hwmod *oh, const char *name)
  */
 static int _assert_hardreset(struct omap_hwmod *oh, const char *name)
 {
-	u8 shift;
+	struct omap_hwmod_rst_info r;
+	u8 ret;
 
 	if (!oh)
 		return -EINVAL;
 
-	shift = _lookup_hardreset(oh, name);
-	if (IS_ERR_VALUE(shift))
-		return shift;
+	ret = _lookup_hardreset(oh, name, &r);
+	if (IS_ERR_VALUE(ret))
+		return ret;
 
 	if (cpu_is_omap24xx() || cpu_is_omap34xx())
 		return omap2_prm_assert_hardreset(oh->prcm.omap2.module_offs,
-						  shift);
+						  r.rst_shift);
 	else if (cpu_is_omap44xx())
 		return omap4_prm_assert_hardreset(oh->prcm.omap4.rstctrl_reg,
-						  shift);
+						  r.rst_shift);
 	else
 		return -EINVAL;
 }
@@ -1040,29 +1045,29 @@ static int _assert_hardreset(struct omap_hwmod *oh, const char *name)
  */
 static int _deassert_hardreset(struct omap_hwmod *oh, const char *name)
 {
-	u8 shift;
-	int r;
+	struct omap_hwmod_rst_info r;
+	int ret;
 
 	if (!oh)
 		return -EINVAL;
 
-	shift = _lookup_hardreset(oh, name);
-	if (IS_ERR_VALUE(shift))
-		return shift;
+	ret = _lookup_hardreset(oh, name, &r);
+	if (IS_ERR_VALUE(ret))
+		return ret;
 
 	if (cpu_is_omap24xx() || cpu_is_omap34xx())
-		r = omap2_prm_deassert_hardreset(oh->prcm.omap2.module_offs,
-						 shift);
+		ret = omap2_prm_deassert_hardreset(oh->prcm.omap2.module_offs,
+						 r.rst_shift, r.st_shift);
 	else if (cpu_is_omap44xx())
-		r = omap4_prm_deassert_hardreset(oh->prcm.omap4.rstctrl_reg,
-						 shift);
+		ret = omap4_prm_deassert_hardreset(oh->prcm.omap4.rstctrl_reg,
+						 r.rst_shift);
 	else
 		return -EINVAL;
 
-	if (r == -EBUSY)
+	if (ret == -EBUSY)
 		pr_warning("omap_hwmod: %s: failed to hardreset\n", oh->name);
 
-	return r;
+	return ret;
 }
 
 /**
@@ -1075,21 +1080,22 @@ static int _deassert_hardreset(struct omap_hwmod *oh, const char *name)
  */
 static int _read_hardreset(struct omap_hwmod *oh, const char *name)
 {
-	u8 shift;
+	struct omap_hwmod_rst_info r;
+	u8 ret;
 
 	if (!oh)
 		return -EINVAL;
 
-	shift = _lookup_hardreset(oh, name);
-	if (IS_ERR_VALUE(shift))
-		return shift;
+	ret = _lookup_hardreset(oh, name, &r);
+	if (IS_ERR_VALUE(ret))
+		return ret;
 
 	if (cpu_is_omap24xx() || cpu_is_omap34xx()) {
 		return omap2_prm_is_hardreset_asserted(oh->prcm.omap2.module_offs,
-						       shift);
+						       r.st_shift);
 	} else if (cpu_is_omap44xx()) {
 		return omap4_prm_is_hardreset_asserted(oh->prcm.omap4.rstctrl_reg,
-						       shift);
+						       r.rst_shift);
 	} else {
 		return -EINVAL;
 	}
diff --git a/arch/arm/mach-omap2/prm2xxx_3xxx.c b/arch/arm/mach-omap2/prm2xxx_3xxx.c
index ec03625..051213f 100644
--- a/arch/arm/mach-omap2/prm2xxx_3xxx.c
+++ b/arch/arm/mach-omap2/prm2xxx_3xxx.c
@@ -118,7 +118,8 @@ int omap2_prm_assert_hardreset(s16 prm_mod, u8 shift)
 /**
  * omap2_prm_deassert_hardreset - deassert a submodule hardreset line and wait
  * @prm_mod: PRM submodule base (e.g. CORE_MOD)
- * @shift: register bit shift corresponding to the reset line to deassert
+ * @rst_shift: register bit shift corresponding to the reset line to deassert
+ * @st_shift: register bit shift for the status of the deasserted submodule
  *
  * Some IPs like dsp or iva contain processors that require an HW
  * reset line to be asserted / deasserted in order to fully enable the
@@ -129,27 +130,28 @@ int omap2_prm_assert_hardreset(s16 prm_mod, u8 shift)
  * -EINVAL upon an argument error, -EEXIST if the submodule was already out
  * of reset, or -EBUSY if the submodule did not exit reset promptly.
  */
-int omap2_prm_deassert_hardreset(s16 prm_mod, u8 shift)
+int omap2_prm_deassert_hardreset(s16 prm_mod, u8 rst_shift, u8 st_shift)
 {
-	u32 mask;
+	u32 rst, st;
 	int c;
 
 	if (!(cpu_is_omap24xx() || cpu_is_omap34xx()))
 		return -EINVAL;
 
-	mask = 1 << shift;
+	rst = 1 << rst_shift;
+	st = 1 << st_shift;
 
 	/* Check the current status to avoid de-asserting the line twice */
-	if (omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTCTRL, mask) == 0)
+	if (omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTCTRL, rst) == 0)
 		return -EEXIST;
 
 	/* Clear the reset status by writing 1 to the status bit */
-	omap2_prm_rmw_mod_reg_bits(0xffffffff, mask, prm_mod, OMAP2_RM_RSTST);
+	omap2_prm_rmw_mod_reg_bits(0xffffffff, st, prm_mod, OMAP2_RM_RSTST);
 	/* de-assert the reset control line */
-	omap2_prm_rmw_mod_reg_bits(mask, 0, prm_mod, OMAP2_RM_RSTCTRL);
+	omap2_prm_rmw_mod_reg_bits(rst, 0, prm_mod, OMAP2_RM_RSTCTRL);
 	/* wait the status to be set */
 	omap_test_timeout(omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTST,
-						  mask),
+						  st),
 			  MAX_MODULE_HARDRESET_WAIT, c);
 
 	return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
diff --git a/arch/arm/mach-omap2/prm2xxx_3xxx.h b/arch/arm/mach-omap2/prm2xxx_3xxx.h
index 49654c8..a1fc62a 100644
--- a/arch/arm/mach-omap2/prm2xxx_3xxx.h
+++ b/arch/arm/mach-omap2/prm2xxx_3xxx.h
@@ -282,7 +282,8 @@ static inline int omap2_prm_assert_hardreset(s16 prm_mod, u8 shift)
 		"not suppose to be used on omap4\n");
 	return 0;
 }
-static inline int omap2_prm_deassert_hardreset(s16 prm_mod, u8 shift)
+static inline int omap2_prm_deassert_hardreset(s16 prm_mod, u8 rst_shift,
+						u8 st_shift)
 {
 	WARN(1, "prm: omap2xxx/omap3xxx specific function and "
 		"not suppose to be used on omap4\n");
@@ -300,7 +301,7 @@ extern u32 omap2_prm_read_mod_bits_shift(s16 domain, s16 idx, u32 mask);
 /* These omap2_ PRM functions apply to both OMAP2 and 3 */
 extern int omap2_prm_is_hardreset_asserted(s16 prm_mod, u8 shift);
 extern int omap2_prm_assert_hardreset(s16 prm_mod, u8 shift);
-extern int omap2_prm_deassert_hardreset(s16 prm_mod, u8 shift);
+extern int omap2_prm_deassert_hardreset(s16 prm_mod, u8 rst_shift, u8 st_shift);
 
 #endif	/* CONFIG_ARCH_OMAP4 */
 #endif
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index 1eee85a..28596b7 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -124,6 +124,7 @@ struct omap_hwmod_dma_info {
  * struct omap_hwmod_rst_info - IPs reset lines use by hwmod
  * @name: name of the reset line (module local name)
  * @rst_shift: Offset of the reset bit
+ * @st_shift: Offset of the reset status bit
  *
  * @name should be something short, e.g., "cpu0" or "rst". It is defined
  * locally to the hwmod.
@@ -131,6 +132,7 @@ struct omap_hwmod_dma_info {
 struct omap_hwmod_rst_info {
 	const char	*name;
 	u8		rst_shift;
+	u8		st_shift;
 };
 
 /**
-- 
1.7.1




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