[PATCH 08/13] ARM: OMAP2+: CM/clock: convert _omap2_module_wait_ready() to use SoC-independent CM functions

Paul Walmsley paul at pwsan.com
Thu Nov 8 17:15:46 EST 2012


On Thu, 25 Oct 2012, Paul Walmsley wrote:

> Convert the OMAP clock code's _omap2_module_wait_ready() to use
> SoC-independent CM functions that are provided by the CM code, rather
> than using a deprecated function from mach-omap2/prcm.c.
> 
> This facilitates the future conversion of the CM code to a driver, and
> also removes a mach-omap2/prcm.c user.  mach-omap2/prcm.c will be removed
> by a subsequent patch.
> 
> Signed-off-by: Paul Walmsley <paul at pwsan.com>

Here's an update of this one.  Further testing with the AM3517/3505 boards 
resulted in a warning message being logged from _omap2_wait_module_ready() 
for emac_ick.  The AM3517 designers didn't integrate the IPSS IDLEST bits 
into the CM as other OMAPs do.  They just put them into the SCM module.  
This shortcut taken during hardware integration just resulted in more time 
wasted on the software side :-(


- Paul

From: Paul Walmsley <paul at pwsan.com>
Date: Mon, 29 Oct 2012 20:56:29 -0600
Subject: [PATCH] ARM: OMAP2+: CM/clock: convert _omap2_module_wait_ready() to
 use SoC-independent CM functions

Convert the OMAP clock code's _omap2_module_wait_ready() to use
SoC-independent CM functions that are provided by the CM code, rather
than using a deprecated function from mach-omap2/prcm.c.

This facilitates the future conversion of the CM code to a driver, and
also removes a mach-omap2/prcm.c user.  mach-omap2/prcm.c will be removed
by a subsequent patch.

Some modules have IDLEST registers that aren't in the CM module, such
as the AM3517 IDLEST bits.  So we also need a fallback function for
these non-CM odd cases.  Create a temporary one in mach-omap2/clock.c,
intended to exist until the SCM drivers are ready.

Signed-off-by: Paul Walmsley <paul at pwsan.com>
Tested-by: Vaibhav Hiremath <hvaibhav at ti.com>
---
 arch/arm/mach-omap2/clock.c     |   56 +++++++++++++++++++++++++++++++--
 arch/arm/mach-omap2/cm.h        |   12 ++++++-
 arch/arm/mach-omap2/cm2xxx.c    |   65 ++++++++++++++++++++++++++++++++++++++
 arch/arm/mach-omap2/cm2xxx.h    |    4 +++
 arch/arm/mach-omap2/cm3xxx.c    |   66 +++++++++++++++++++++++++++++++++++++++
 arch/arm/mach-omap2/cm3xxx.h    |    5 +++
 arch/arm/mach-omap2/cm_common.c |   48 ++++++++++++++++++++++++++++
 arch/arm/mach-omap2/io.c        |    5 +++
 8 files changed, 257 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c
index 9205ea7..2fe57d6 100644
--- a/arch/arm/mach-omap2/clock.c
+++ b/arch/arm/mach-omap2/clock.c
@@ -33,10 +33,18 @@
 #include "soc.h"
 #include "clockdomain.h"
 #include "clock.h"
+#include "cm.h"
 #include "cm2xxx.h"
 #include "cm3xxx.h"
 #include "cm-regbits-24xx.h"
 #include "cm-regbits-34xx.h"
+#include "common.h"
+
+/*
+ * MAX_MODULE_ENABLE_WAIT: maximum of number of microseconds to wait
+ * for a module to indicate that it is no longer in idle
+ */
+#define MAX_MODULE_ENABLE_WAIT		100000
 
 u16 cpu_mask;
 
@@ -58,6 +66,40 @@ static DEFINE_SPINLOCK(clockfw_lock);
 
 /* Private functions */
 
+
+/**
+ * _wait_idlest_generic - wait for a module to leave the idle state
+ * @reg: virtual address of module IDLEST register
+ * @mask: value to mask against to determine if the module is active
+ * @idlest: idle state indicator (0 or 1) for the clock
+ * @name: name of the clock (for printk)
+ *
+ * Wait for a module to leave idle, where its idle-status register is
+ * not inside the CM module.  Returns 1 if the module left idle
+ * promptly, or 0 if the module did not leave idle before the timeout
+ * elapsed.  XXX Deprecated - should be moved into drivers for the
+ * individual IP block that the IDLEST register exists in.
+ */
+static int _wait_idlest_generic(void __iomem *reg, u32 mask, u8 idlest,
+				const char *name)
+{
+	int i = 0, ena = 0;
+
+	ena = (idlest) ? 0 : mask;
+
+	omap_test_timeout(((__raw_readl(reg) & mask) == ena),
+			  MAX_MODULE_ENABLE_WAIT, i);
+
+	if (i < MAX_MODULE_ENABLE_WAIT)
+		pr_debug("omap clock: module associated with clock %s ready after %d loops\n",
+			 name, i);
+	else
+		pr_err("omap clock: module associated with clock %s didn't enable in %d tries\n",
+		       name, MAX_MODULE_ENABLE_WAIT);
+
+	return (i < MAX_MODULE_ENABLE_WAIT) ? 1 : 0;
+};
+
 /**
  * _omap2_module_wait_ready - wait for an OMAP module to leave IDLE
  * @clk: struct clk * belonging to the module
@@ -71,7 +113,9 @@ static DEFINE_SPINLOCK(clockfw_lock);
 static void _omap2_module_wait_ready(struct clk *clk)
 {
 	void __iomem *companion_reg, *idlest_reg;
-	u8 other_bit, idlest_bit, idlest_val;
+	u8 other_bit, idlest_bit, idlest_val, idlest_reg_id;
+	s16 prcm_mod;
+	int r;
 
 	/* Not all modules have multiple clocks that their IDLEST depends on */
 	if (clk->ops->find_companion) {
@@ -82,8 +126,14 @@ static void _omap2_module_wait_ready(struct clk *clk)
 
 	clk->ops->find_idlest(clk, &idlest_reg, &idlest_bit, &idlest_val);
 
-	omap2_cm_wait_idlest(idlest_reg, (1 << idlest_bit), idlest_val,
-			     __clk_get_name(clk));
+	r = cm_split_idlest_reg(idlest_reg, &prcm_mod, &idlest_reg_id);
+	if (r) {
+		/* IDLEST register not in the CM module */
+		_wait_idlest_generic(idlest_reg, (1 << idlest_bit), idlest_val,
+				     clk->name);
+	} else {
+		cm_wait_module_ready(prcm_mod, idlest_reg_id, idlest_bit);
+	};
 }
 
 /* Public functions */
diff --git a/arch/arm/mach-omap2/cm.h b/arch/arm/mach-omap2/cm.h
index b3cee91..e419ecb 100644
--- a/arch/arm/mach-omap2/cm.h
+++ b/arch/arm/mach-omap2/cm.h
@@ -37,8 +37,18 @@
 
 /**
  * struct cm_ll_data - fn ptrs to per-SoC CM function implementations
+ * @split_idlest_reg: ptr to the SoC CM-specific split_idlest_reg impl
+ * @wait_module_ready: ptr to the SoC CM-specific wait_module_ready impl
  */
-struct cm_ll_data {};
+struct cm_ll_data {
+	int (*split_idlest_reg)(void __iomem *idlest_reg, s16 *prcm_inst,
+				u8 *idlest_reg_id);
+	int (*wait_module_ready)(s16 prcm_mod, u8 idlest_id, u8 idlest_shift);
+};
+
+extern int cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
+			       u8 *idlest_reg_id);
+extern int cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift);
 
 extern int cm_register(struct cm_ll_data *cld);
 extern int cm_unregister(struct cm_ll_data *cld);
diff --git a/arch/arm/mach-omap2/cm2xxx.c b/arch/arm/mach-omap2/cm2xxx.c
index e96cd70..db65069 100644
--- a/arch/arm/mach-omap2/cm2xxx.c
+++ b/arch/arm/mach-omap2/cm2xxx.c
@@ -198,6 +198,43 @@ void omap2xxx_cm_apll96_disable(void)
 	_omap2xxx_apll_disable(OMAP24XX_EN_96M_PLL_SHIFT);
 }
 
+/**
+ * omap2xxx_cm_split_idlest_reg - split CM_IDLEST reg addr into its components
+ * @idlest_reg: CM_IDLEST* virtual address
+ * @prcm_inst: pointer to an s16 to return the PRCM instance offset
+ * @idlest_reg_id: pointer to a u8 to return the CM_IDLESTx register ID
+ *
+ * XXX This function is only needed until absolute register addresses are
+ * removed from the OMAP struct clk records.
+ */
+int omap2xxx_cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
+				 u8 *idlest_reg_id)
+{
+	unsigned long offs;
+	u8 idlest_offs;
+	int i;
+
+	if (idlest_reg < cm_base || idlest_reg > (cm_base + 0x0fff))
+		return -EINVAL;
+
+	idlest_offs = (unsigned long)idlest_reg & 0xff;
+	for (i = 0; i < ARRAY_SIZE(omap2xxx_cm_idlest_offs); i++) {
+		if (idlest_offs == omap2xxx_cm_idlest_offs[i]) {
+			*idlest_reg_id = i + 1;
+			break;
+		}
+	}
+
+	if (i == ARRAY_SIZE(omap2xxx_cm_idlest_offs))
+		return -EINVAL;
+
+	offs = idlest_reg - cm_base;
+	offs &= 0xff00;
+	*prcm_inst = offs;
+
+	return 0;
+}
+
 /*
  *
  */
@@ -314,3 +351,31 @@ struct clkdm_ops omap2_clkdm_operations = {
 	.clkdm_clk_enable	= omap2xxx_clkdm_clk_enable,
 	.clkdm_clk_disable	= omap2xxx_clkdm_clk_disable,
 };
+
+/*
+ *
+ */
+
+static struct cm_ll_data omap2xxx_cm_ll_data = {
+	.split_idlest_reg	= &omap2xxx_cm_split_idlest_reg,
+	.wait_module_ready	= &omap2xxx_cm_wait_module_ready,
+};
+
+int __init omap2xxx_cm_init(void)
+{
+	if (!cpu_is_omap24xx())
+		return 0;
+
+	return cm_register(&omap2xxx_cm_ll_data);
+}
+
+static void __exit omap2xxx_cm_exit(void)
+{
+	if (!cpu_is_omap24xx())
+		return;
+
+	/* Should never happen */
+	WARN(cm_unregister(&omap2xxx_cm_ll_data),
+	     "%s: cm_ll_data function pointer mismatch\n", __func__);
+}
+__exitcall(omap2xxx_cm_exit);
diff --git a/arch/arm/mach-omap2/cm2xxx.h b/arch/arm/mach-omap2/cm2xxx.h
index bce3c4b..4cbb39b 100644
--- a/arch/arm/mach-omap2/cm2xxx.h
+++ b/arch/arm/mach-omap2/cm2xxx.h
@@ -60,6 +60,10 @@ extern void omap2xxx_cm_set_apll96_auto_low_power_stop(void);
 extern bool omap2xxx_cm_is_clkdm_in_hwsup(s16 module, u32 mask);
 extern int omap2xxx_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id,
 					 u8 idlest_shift);
+extern int omap2xxx_cm_split_idlest_reg(void __iomem *idlest_reg,
+					s16 *prcm_inst, u8 *idlest_reg_id);
+
+extern int __init omap2xxx_cm_init(void);
 
 #endif
 
diff --git a/arch/arm/mach-omap2/cm3xxx.c b/arch/arm/mach-omap2/cm3xxx.c
index 8b03ec2..c2086f2 100644
--- a/arch/arm/mach-omap2/cm3xxx.c
+++ b/arch/arm/mach-omap2/cm3xxx.c
@@ -110,6 +110,44 @@ int omap3xxx_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift)
 	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
 }
 
+/**
+ * omap3xxx_cm_split_idlest_reg - split CM_IDLEST reg addr into its components
+ * @idlest_reg: CM_IDLEST* virtual address
+ * @prcm_inst: pointer to an s16 to return the PRCM instance offset
+ * @idlest_reg_id: pointer to a u8 to return the CM_IDLESTx register ID
+ *
+ * XXX This function is only needed until absolute register addresses are
+ * removed from the OMAP struct clk records.
+ */
+int omap3xxx_cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
+				 u8 *idlest_reg_id)
+{
+	unsigned long offs;
+	u8 idlest_offs;
+	int i;
+
+	if (idlest_reg < (cm_base + OMAP3430_IVA2_MOD) ||
+	    idlest_reg > (cm_base + 0x1ffff))
+		return -EINVAL;
+
+	idlest_offs = (unsigned long)idlest_reg & 0xff;
+	for (i = 0; i < ARRAY_SIZE(omap3xxx_cm_idlest_offs); i++) {
+		if (idlest_offs == omap3xxx_cm_idlest_offs[i]) {
+			*idlest_reg_id = i + 1;
+			break;
+		}
+	}
+
+	if (i == ARRAY_SIZE(omap3xxx_cm_idlest_offs))
+		return -EINVAL;
+
+	offs = idlest_reg - cm_base;
+	offs &= 0xff00;
+	*prcm_inst = offs;
+
+	return 0;
+}
+
 /* Clockdomain low-level operations */
 
 static int omap3xxx_clkdm_add_sleepdep(struct clockdomain *clkdm1,
@@ -597,3 +635,31 @@ void omap3_cm_restore_context(void)
 	omap2_cm_write_mod_reg(cm_context.cm_clkout_ctrl, OMAP3430_CCR_MOD,
 			       OMAP3_CM_CLKOUT_CTRL_OFFSET);
 }
+
+/*
+ *
+ */
+
+static struct cm_ll_data omap3xxx_cm_ll_data = {
+	.split_idlest_reg	= &omap3xxx_cm_split_idlest_reg,
+	.wait_module_ready	= &omap3xxx_cm_wait_module_ready,
+};
+
+int __init omap3xxx_cm_init(void)
+{
+	if (!cpu_is_omap34xx())
+		return 0;
+
+	return cm_register(&omap3xxx_cm_ll_data);
+}
+
+static void __exit omap3xxx_cm_exit(void)
+{
+	if (!cpu_is_omap34xx())
+		return;
+
+	/* Should never happen */
+	WARN(cm_unregister(&omap3xxx_cm_ll_data),
+	     "%s: cm_ll_data function pointer mismatch\n", __func__);
+}
+__exitcall(omap3xxx_cm_exit);
diff --git a/arch/arm/mach-omap2/cm3xxx.h b/arch/arm/mach-omap2/cm3xxx.h
index 4a6ac81..e8e146f 100644
--- a/arch/arm/mach-omap2/cm3xxx.h
+++ b/arch/arm/mach-omap2/cm3xxx.h
@@ -78,9 +78,14 @@ extern bool omap3xxx_cm_is_clkdm_in_hwsup(s16 module, u32 mask);
 extern int omap3xxx_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id,
 					 u8 idlest_shift);
 
+extern int omap3xxx_cm_split_idlest_reg(void __iomem *idlest_reg,
+					s16 *prcm_inst, u8 *idlest_reg_id);
+
 extern void omap3_cm_save_context(void);
 extern void omap3_cm_restore_context(void);
 
+extern int __init omap3xxx_cm_init(void);
+
 #endif
 
 #endif
diff --git a/arch/arm/mach-omap2/cm_common.c b/arch/arm/mach-omap2/cm_common.c
index 3246cef..561969b 100644
--- a/arch/arm/mach-omap2/cm_common.c
+++ b/arch/arm/mach-omap2/cm_common.c
@@ -26,6 +26,54 @@ static struct cm_ll_data null_cm_ll_data;
 static struct cm_ll_data *cm_ll_data = &null_cm_ll_data;
 
 /**
+ * cm_split_idlest_reg - split CM_IDLEST reg addr into its components
+ * @idlest_reg: CM_IDLEST* virtual address
+ * @prcm_inst: pointer to an s16 to return the PRCM instance offset
+ * @idlest_reg_id: pointer to a u8 to return the CM_IDLESTx register ID
+ *
+ * Given an absolute CM_IDLEST register address @idlest_reg, passes
+ * the PRCM instance offset and IDLEST register ID back to the caller
+ * via the @prcm_inst and @idlest_reg_id.  Returns -EINVAL upon error,
+ * or 0 upon success.  XXX This function is only needed until absolute
+ * register addresses are removed from the OMAP struct clk records.
+ */
+int cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
+			u8 *idlest_reg_id)
+{
+	if (!cm_ll_data->split_idlest_reg) {
+		WARN_ONCE(1, "cm: %s: no low-level function defined\n",
+			  __func__);
+		return -EINVAL;
+	}
+
+	return cm_ll_data->split_idlest_reg(idlest_reg, prcm_inst,
+					   idlest_reg_id);
+}
+
+/**
+ * cm_wait_module_ready - wait for a module to leave idle or standby
+ * @prcm_mod: PRCM module offset
+ * @idlest_id: CM_IDLESTx register ID (i.e., x = 1, 2, 3)
+ * @idlest_shift: shift of the bit in the CM_IDLEST* register to check
+ *
+ * Wait for the PRCM to indicate that the module identified by
+ * (@prcm_mod, @idlest_id, @idlest_shift) is clocked.  Return 0 upon
+ * success, -EBUSY if the module doesn't enable in time, or -EINVAL if
+ * no per-SoC wait_module_ready() function pointer has been registered
+ * or if the idlest register is unknown on the SoC.
+ */
+int cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift)
+{
+	if (!cm_ll_data->wait_module_ready) {
+		WARN_ONCE(1, "cm: %s: no low-level function defined\n",
+			  __func__);
+		return -EINVAL;
+	}
+
+	return cm_ll_data->wait_module_ready(prcm_mod, idlest_id, idlest_shift);
+}
+
+/**
  * cm_register - register per-SoC low-level data with the CM
  * @cld: low-level per-SoC OMAP CM data & function pointers to register
  *
diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c
index a204b70..772dc7e 100644
--- a/arch/arm/mach-omap2/io.c
+++ b/arch/arm/mach-omap2/io.c
@@ -45,6 +45,8 @@
 #include "sdrc.h"
 #include "control.h"
 #include "serial.h"
+#include "cm2xxx.h"
+#include "cm3xxx.h"
 
 /*
  * The machine specific code may provide the extra mapping besides the
@@ -388,6 +390,7 @@ void __init omap2420_init_early(void)
 			       OMAP2_L4_IO_ADDRESS(OMAP2420_CM_BASE),
 			       NULL, NULL);
 	omap2xxx_check_revision();
+	omap2xxx_cm_init();
 	omap_common_init_early();
 	omap2xxx_voltagedomains_init();
 	omap242x_powerdomains_init();
@@ -417,6 +420,7 @@ void __init omap2430_init_early(void)
 			       OMAP2_L4_IO_ADDRESS(OMAP2430_CM_BASE),
 			       NULL, NULL);
 	omap2xxx_check_revision();
+	omap2xxx_cm_init();
 	omap_common_init_early();
 	omap2xxx_voltagedomains_init();
 	omap243x_powerdomains_init();
@@ -451,6 +455,7 @@ void __init omap3_init_early(void)
 			       NULL, NULL);
 	omap3xxx_check_revision();
 	omap3xxx_check_features();
+	omap3xxx_cm_init();
 	omap_common_init_early();
 	omap3xxx_voltagedomains_init();
 	omap3xxx_powerdomains_init();
-- 
1.7.10.4




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