Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 33 insertions, 63 deletions

diff --git a/drivers/clk/at91/clk-system.c b/drivers/clk/at91/clk-system.c
index 3f5314344286..8f35d8172909 100644
--- a/drivers/clk/at91/clk-system.c
+++ b/drivers/clk/at91/clk-system.c
@@ -12,13 +12,8 @@
 #include <linux/clkdev.h>
 #include <linux/clk/at91_pmc.h>
 #include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/io.h>
-#include <linux/irq.h>
-#include <linux/of_irq.h>
-#include <linux/interrupt.h>
-#include <linux/wait.h>
-#include <linux/sched.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
 
 #include "pmc.h"
 
@@ -29,9 +24,7 @@
 #define to_clk_system(hw) container_of(hw, struct clk_system, hw)
 struct clk_system {
 	struct clk_hw hw;
-	struct at91_pmc *pmc;
-	unsigned int irq;
-	wait_queue_head_t wait;
+	struct regmap *regmap;
 	u8 id;
 };
 
@@ -39,58 +32,54 @@ static inline int is_pck(int id)
 {
 	return (id >= 8) && (id <= 15);
 }
-static irqreturn_t clk_system_irq_handler(int irq, void *dev_id)
+
+static inline bool clk_system_ready(struct regmap *regmap, int id)
 {
-	struct clk_system *sys = (struct clk_system *)dev_id;
+	unsigned int status;
 
-	wake_up(&sys->wait);
-	disable_irq_nosync(sys->irq);
+	regmap_read(regmap, AT91_PMC_SR, &status);
 
-	return IRQ_HANDLED;
+	return status & (1 << id) ? 1 : 0;
 }
 
 static int clk_system_prepare(struct clk_hw *hw)
 {
 	struct clk_system *sys = to_clk_system(hw);
-	struct at91_pmc *pmc = sys->pmc;
-	u32 mask = 1 << sys->id;
 
-	pmc_write(pmc, AT91_PMC_SCER, mask);
+	regmap_write(sys->regmap, AT91_PMC_SCER, 1 << sys->id);
 
 	if (!is_pck(sys->id))
 		return 0;
 
-	while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) {
-		if (sys->irq) {
-			enable_irq(sys->irq);
-			wait_event(sys->wait,
-				   pmc_read(pmc, AT91_PMC_SR) & mask);
-		} else
-			cpu_relax();
-	}
+	while (!clk_system_ready(sys->regmap, sys->id))
+		cpu_relax();
+
 	return 0;
 }
 
 static void clk_system_unprepare(struct clk_hw *hw)
 {
 	struct clk_system *sys = to_clk_system(hw);
-	struct at91_pmc *pmc = sys->pmc;
 
-	pmc_write(pmc, AT91_PMC_SCDR, 1 << sys->id);
+	regmap_write(sys->regmap, AT91_PMC_SCDR, 1 << sys->id);
 }
 
 static int clk_system_is_prepared(struct clk_hw *hw)
 {
 	struct clk_system *sys = to_clk_system(hw);
-	struct at91_pmc *pmc = sys->pmc;
+	unsigned int status;
+
+	regmap_read(sys->regmap, AT91_PMC_SCSR, &status);
 
-	if (!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id)))
+	if (!(status & (1 << sys->id)))
 		return 0;
 
 	if (!is_pck(sys->id))
 		return 1;
 
-	return !!(pmc_read(pmc, AT91_PMC_SR) & (1 << sys->id));
+	regmap_read(sys->regmap, AT91_PMC_SR, &status);
+
+	return status & (1 << sys->id) ? 1 : 0;
 }
 
 static const struct clk_ops system_ops = {
@@ -100,13 +89,12 @@ static const struct clk_ops system_ops = {
 };
 
 static struct clk * __init
-at91_clk_register_system(struct at91_pmc *pmc, const char *name,
-			 const char *parent_name, u8 id, int irq)
+at91_clk_register_system(struct regmap *regmap, const char *name,
+			 const char *parent_name, u8 id)
 {
 	struct clk_system *sys;
 	struct clk *clk = NULL;
 	struct clk_init_data init;
-	int ret;
 
 	if (!parent_name || id > SYSTEM_MAX_ID)
 		return ERR_PTR(-EINVAL);
@@ -123,44 +111,33 @@ at91_clk_register_system(struct at91_pmc *pmc, const char *name,
 
 	sys->id = id;
 	sys->hw.init = &init;
-	sys->pmc = pmc;
-	sys->irq = irq;
-	if (irq) {
-		init_waitqueue_head(&sys->wait);
-		irq_set_status_flags(sys->irq, IRQ_NOAUTOEN);
-		ret = request_irq(sys->irq, clk_system_irq_handler,
-				IRQF_TRIGGER_HIGH, name, sys);
-		if (ret) {
-			kfree(sys);
-			return ERR_PTR(ret);
-		}
-	}
+	sys->regmap = regmap;
 
 	clk = clk_register(NULL, &sys->hw);
-	if (IS_ERR(clk)) {
-		if (irq)
-			free_irq(sys->irq, sys);
+	if (IS_ERR(clk))
 		kfree(sys);
-	}
 
 	return clk;
 }
 
-static void __init
-of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
+static void __init of_at91rm9200_clk_sys_setup(struct device_node *np)
 {
 	int num;
-	int irq = 0;
 	u32 id;
 	struct clk *clk;
 	const char *name;
 	struct device_node *sysclknp;
 	const char *parent_name;
+	struct regmap *regmap;
 
 	num = of_get_child_count(np);
 	if (num > (SYSTEM_MAX_ID + 1))
 		return;
 
+	regmap = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap))
+		return;
+
 	for_each_child_of_node(np, sysclknp) {
 		if (of_property_read_u32(sysclknp, "reg", &id))
 			continue;
@@ -168,21 +145,14 @@ of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
 		if (of_property_read_string(np, "clock-output-names", &name))
 			name = sysclknp->name;
 
-		if (is_pck(id))
-			irq = irq_of_parse_and_map(sysclknp, 0);
-
 		parent_name = of_clk_get_parent_name(sysclknp, 0);
 
-		clk = at91_clk_register_system(pmc, name, parent_name, id, irq);
+		clk = at91_clk_register_system(regmap, name, parent_name, id);
 		if (IS_ERR(clk))
 			continue;
 
 		of_clk_add_provider(sysclknp, of_clk_src_simple_get, clk);
 	}
 }
-
-void __init of_at91rm9200_clk_sys_setup(struct device_node *np,
-					struct at91_pmc *pmc)
-{
-	of_at91_clk_sys_setup(np, pmc);
-}
+CLK_OF_DECLARE(at91rm9200_clk_sys, "atmel,at91rm9200-clk-system",
+	       of_at91rm9200_clk_sys_setup);