Re: [PATCHv5 11/35] ARM: OMAP2+: clock: move clock provider infrastructure to clock driver

[Tero Kristo <t-kristo@ti.com>]

Hi,

Tony had a small comment about this patch, so I made a slightly modified 
version where the direct reg access (not through memmap) is dropped; it 
is no longer needed as the legacy omap3 clock data was moved under TI 
clock driver. I force pushed this patch to the v5 branch, the modified 
patch inlined below. Check the implementation for omap2_clk_readl / 
omap2_clk_writel, and the updated ti_clk_ll_ops.

-Tero

---
 From 0fdee64696a7500bb15f07aa3dfd70a3b27e1c94 Mon Sep 17 00:00:00 2001
From: Tero Kristo <t-kristo@ti.com>
Date: Wed, 22 Oct 2014 15:15:36 +0300
Subject: [PATCH 11/35] ARM: OMAP2+: clock: move clock provider 
infrastructure
  to clock driver

Splits the clock provider init out of the PRM driver and moves it to
clock driver. This is needed so that once the PRCM drivers are separated,
they can logically just access the clock driver not needing to go through
common PRM code. This would be wrong in the case of control module for
example.

This patch also removes the legacy direct clk_readl / clk_writel support
(not going through memmaps) as this is no longer needed.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
---
  arch/arm/mach-omap2/clock.c      |   67 
++++++++++++++++++++++++++++----------
  arch/arm/mach-omap2/clock.h      |   21 +++++++++---
  arch/arm/mach-omap2/prm_common.c |   36 +++++---------------
  3 files changed, 75 insertions(+), 49 deletions(-)

diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c
index 6124db5..e320850 100644
--- a/arch/arm/mach-omap2/clock.c
+++ b/arch/arm/mach-omap2/clock.c
@@ -23,6 +23,7 @@
  #include <linux/clk-provider.h>
  #include <linux/io.h>
  #include <linux/bitops.h>
+#include <linux/of_address.h>
  #include <asm/cpu.h>

  #include <trace/events/power.h>
@@ -72,30 +73,62 @@ struct ti_clk_features ti_clk_features;
  static bool clkdm_control = true;

  static LIST_HEAD(clk_hw_omap_clocks);
-void __iomem *clk_memmaps[CLK_MAX_MEMMAPS];
+static void __iomem *clk_memmaps[CLK_MAX_MEMMAPS];

-void omap2_clk_writel(u32 val, struct clk_hw_omap *clk, void __iomem *reg)
+void omap2_clk_memmap_writel(u32 val, void __iomem *reg)
  {
-	if (clk->flags & MEMMAP_ADDRESSING) {
-		struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
-		writel_relaxed(val, clk_memmaps[r->index] + r->offset);
-	} else {
-		writel_relaxed(val, reg);
-	}
+	struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
+
+	writel_relaxed(val, clk_memmaps[r->index] + r->offset);
  }

-u32 omap2_clk_readl(struct clk_hw_omap *clk, void __iomem *reg)
+u32 omap2_clk_memmap_readl(void __iomem *reg)
  {
-	u32 val;
+	struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;

-	if (clk->flags & MEMMAP_ADDRESSING) {
-		struct clk_omap_reg *r = (struct clk_omap_reg *)&reg;
-		val = readl_relaxed(clk_memmaps[r->index] + r->offset);
-	} else {
-		val = readl_relaxed(reg);
-	}
+	return readl_relaxed(clk_memmaps[r->index] + r->offset);
+}
+
+static struct ti_clk_ll_ops omap_clk_ll_ops = {
+	.clk_readl = omap2_clk_memmap_readl,
+	.clk_writel = omap2_clk_memmap_writel,
+};
+
+/**
+ * omap2_clk_provider_init - initialize a clock provider
+ * @match_table: DT device table to match for devices to init
+ * @np: device node pointer for the this clock provider
+ * @index: index for the clock provider
+ * @mem: iomem pointer for the clock provider memory area
+ *
+ * Initializes a clock provider module (CM/PRM etc.), registering
+ * the memory mapping at specified index and initializing the
+ * low level driver infrastructure. Returns 0 in success.
+ */
+int __init omap2_clk_provider_init(struct device_node *np, int index,
+				   void __iomem *mem)
+{
+	ti_clk_ll_ops = &omap_clk_ll_ops;
+
+	clk_memmaps[index] = mem;
+
+	ti_dt_clk_init_provider(np, index);
+
+	return 0;
+}
+
+/**
+ * omap2_clk_legacy_provider_init - initialize a legacy clock provider
+ * @index: index for the clock provider
+ * @mem: iomem pointer for the clock provider memory area
+ *
+ * Initializes a legacy clock provider memory mapping.
+ */
+void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
+{
+	ti_clk_ll_ops = &omap_clk_ll_ops;

-	return val;
+	clk_memmaps[index] = mem;
  }

  /*
diff --git a/arch/arm/mach-omap2/clock.h b/arch/arm/mach-omap2/clock.h
index a56742f..ac2c3d6 100644
--- a/arch/arm/mach-omap2/clock.h
+++ b/arch/arm/mach-omap2/clock.h
@@ -220,8 +220,19 @@ void omap2_clk_print_new_rates(const char 
*hfclkin_ck_name,
  			       const char *core_ck_name,
  			       const char *mpu_ck_name);

-u32 omap2_clk_readl(struct clk_hw_omap *clk, void __iomem *reg);
-void omap2_clk_writel(u32 val, struct clk_hw_omap *clk, void __iomem *reg);
+void omap2_clk_memmap_writel(u32 val, void __iomem *reg);
+u32 omap2_clk_memmap_readl(void __iomem *reg);
+
+static inline u32 omap2_clk_readl(struct clk_hw_omap *clk, void __iomem 
*reg)
+{
+	return omap2_clk_memmap_readl(reg);
+}
+
+static inline void omap2_clk_writel(u32 val, struct clk_hw_omap *clk,
+				    void __iomem *reg)
+{
+	omap2_clk_memmap_writel(val, reg);
+}

  extern u16 cpu_mask;

@@ -271,10 +282,12 @@ extern const struct clksel_rate div_1_3_rates[];
  extern const struct clksel_rate div_1_4_rates[];
  extern const struct clksel_rate div31_1to31_rates[];

-extern void __iomem *clk_memmaps[];
-
  extern int omap2_clkops_enable_clkdm(struct clk_hw *hw);
  extern void omap2_clkops_disable_clkdm(struct clk_hw *hw);

+int __init omap2_clk_provider_init(struct device_node *np, int index,
+				   void __iomem *mem);
+void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem);
+
  void __init ti_clk_init_features(void);
  #endif
diff --git a/arch/arm/mach-omap2/prm_common.c 
b/arch/arm/mach-omap2/prm_common.c
index 8ec5201..1bfd00e 100644
--- a/arch/arm/mach-omap2/prm_common.c
+++ b/arch/arm/mach-omap2/prm_common.c
@@ -677,25 +677,6 @@ static const struct of_device_id 
omap_prcm_dt_match_table[] = {
  	{ }
  };

-static struct clk_hw_omap memmap_dummy_ck = {
-	.flags = MEMMAP_ADDRESSING,
-};
-
-static u32 prm_clk_readl(void __iomem *reg)
-{
-	return omap2_clk_readl(&memmap_dummy_ck, reg);
-}
-
-static void prm_clk_writel(u32 val, void __iomem *reg)
-{
-	omap2_clk_writel(val, &memmap_dummy_ck, reg);
-}
-
-static struct ti_clk_ll_ops omap_clk_ll_ops = {
-	.clk_readl = prm_clk_readl,
-	.clk_writel = prm_clk_writel,
-};
-
  /**
   * omap_prcm_init - low level init for the PRCM drivers
   *
@@ -708,8 +689,7 @@ int __init omap_prcm_init(void)
  	void __iomem *mem;
  	const struct of_device_id *match;
  	const struct omap_prcm_init_data *data;
-
-	ti_clk_ll_ops = &omap_clk_ll_ops;
+	int ret;

  	for_each_matching_node_and_match(np, omap_prcm_dt_match_table, &match) {
  		data = match->data;
@@ -718,8 +698,9 @@ int __init omap_prcm_init(void)
  		if (!mem)
  			return -ENOMEM;

-		clk_memmaps[data->index] = mem;
-		ti_dt_clk_init_provider(np, data->index);
+		ret = omap2_clk_provider_init(np, data->index, mem);
+		if (ret)
+			return ret;
  	}

  	return 0;
@@ -727,11 +708,10 @@ int __init omap_prcm_init(void)

  void __init omap3_prcm_legacy_iomaps_init(void)
  {
-	ti_clk_ll_ops = &omap_clk_ll_ops;
-
-	clk_memmaps[TI_CLKM_CM] = cm_base + OMAP3430_IVA2_MOD;
-	clk_memmaps[TI_CLKM_PRM] = prm_base + OMAP3430_IVA2_MOD;
-	clk_memmaps[TI_CLKM_SCRM] = omap_ctrl_base_get();
+	omap2_clk_legacy_provider_init(TI_CLKM_CM, cm_base + OMAP3430_IVA2_MOD);
+	omap2_clk_legacy_provider_init(TI_CLKM_PRM,
+				       prm_base + OMAP3430_IVA2_MOD);
+	omap2_clk_legacy_provider_init(TI_CLKM_SCRM, omap_ctrl_base_get());
  }

  static int __init prm_late_init(void)
-- 
1.7.9.5