clk: make ICST driver handle the VCO registers

It turns out that all platforms using the ICST VCO are really
just touching two registers, and in the same way as well: one
register with the VCO configuration as such, and one lock register
that makes it possible to write to the VCO.

Factor this register read/write into the ICST driver so we can
reuse it in the IM-PD1 driver.

Signed-off-by: Linus Walleij <[e-mail]>
Signed-off-by: Mike Turquette <[e-mail]>

drivers/clk/versatile/clk-icst.c

···
 #include <linux/clkdev.h>
 #include <linux/err.h>
 #include <linux/clk-provider.h>
+#include <linux/io.h>
 
 #include "clk-icst.h"
 
 /**
  * struct clk_icst - ICST VCO clock wrapper
  * @hw: corresponding clock hardware entry
+ * @vcoreg: VCO register address
+ * @lockreg: VCO lock register address
  * @params: parameters for this ICST instance
  * @rate: current rate
- * @setvco: function to commit ICST settings to hardware
  */
 struct clk_icst {
 	struct clk_hw hw;
+	void __iomem *vcoreg;
+	void __iomem *lockreg;
 	const struct icst_params *params;
 	unsigned long rate;
-	struct icst_vco (*getvco)(void);
-	void (*setvco)(struct icst_vco);
 };
 
 #define to_icst(_hw) container_of(_hw, struct clk_icst, hw)
+
+/**
+ * vco_get() - get ICST VCO settings from a certain register
+ * @vcoreg: register containing the VCO settings
+ */
+static struct icst_vco vco_get(void __iomem *vcoreg)
+{
+	u32 val;
+	struct icst_vco vco;
+
+	val = readl(vcoreg);
+	vco.v = val & 0x1ff;
+	vco.r = (val >> 9) & 0x7f;
+	vco.s = (val >> 16) & 03;
+	return vco;
+}
+
+/**
+ * vco_set() - commit changes to an ICST VCO
+ * @locreg: register to poke to unlock the VCO for writing
+ * @vcoreg: register containing the VCO settings
+ * @vco: ICST VCO parameters to commit
+ */
+static void vco_set(void __iomem *lockreg,
+			void __iomem *vcoreg,
+			struct icst_vco vco)
+{
+	u32 val;
+
+	val = readl(vcoreg) & ~0x7ffff;
+	val |= vco.v | (vco.r << 9) | (vco.s << 16);
+
+	/* This magic unlocks the VCO so it can be controlled */
+	writel(0xa05f, lockreg);
+	writel(val, vcoreg);
+	/* This locks the VCO again */
+	writel(0, lockreg);
+}
+
 
 static unsigned long icst_recalc_rate(struct clk_hw *hw,
 				      unsigned long parent_rate)
···
 	struct clk_icst *icst = to_icst(hw);
 	struct icst_vco vco;
 
-	vco = icst->getvco();
+	vco = vco_get(icst->vcoreg);
 	icst->rate = icst_hz(icst->params, vco);
 	return icst->rate;
 }
···
 
 	vco = icst_hz_to_vco(icst->params, rate);
 	icst->rate = icst_hz(icst->params, vco);
-	icst->setvco(vco);
+	vco_set(icst->vcoreg, icst->lockreg, vco);
 	return 0;
 }
 
···
 	.set_rate = icst_set_rate,
 };
 
-struct clk * __init icst_clk_register(struct device *dev,
-				      const struct clk_icst_desc *desc)
+struct clk *icst_clk_register(struct device *dev,
+			const struct clk_icst_desc *desc,
+			void __iomem *base)
 {
 	struct clk *clk;
 	struct clk_icst *icst;
···
 	init.num_parents = 0;
 	icst->hw.init = &init;
 	icst->params = desc->params;
-	icst->getvco = desc->getvco;
-	icst->setvco = desc->setvco;
+	icst->vcoreg = base + desc->vco_offset;
+	icst->lockreg = base + desc->lock_offset;
 
 	clk = clk_register(dev, &icst->hw);
 	if (IS_ERR(clk))

drivers/clk/versatile/clk-icst.h

···
 #include <asm/hardware/icst.h>
 
+/**
+ * struct clk_icst_desc - descriptor for the ICST VCO
+ * @params: ICST parameters
+ * @vco_offset: offset to the ICST VCO from the provided memory base
+ * @lock_offset: offset to the ICST VCO locking register from the provided
+ *	memory base
+ */
 struct clk_icst_desc {
 	const struct icst_params *params;
-	struct icst_vco (*getvco)(void);
-	void (*setvco)(struct icst_vco);
+	u32 vco_offset;
+	u32 lock_offset;
 };
 
 struct clk *icst_clk_register(struct device *dev,
-			      const struct clk_icst_desc *desc);
+			      const struct clk_icst_desc *desc,
+			      void __iomem *base);

drivers/clk/versatile/clk-integrator.c

···
 #include <linux/clk.h>
 #include <linux/clkdev.h>
 #include <linux/err.h>
-#include <linux/io.h>
+#include <linux/platform_data/clk-integrator.h>
 
 #include <mach/hardware.h>
 #include <mach/platform.h>
···
  * Inspired by portions of:
  * plat-versatile/clock.c and plat-versatile/include/plat/clock.h
  */
-#define CM_LOCK		(__io_address(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_LOCK_OFFSET)
-#define CM_AUXOSC	(__io_address(INTEGRATOR_HDR_BASE)+0x1c)
-
-/**
- * cp_auxvco_get() - get ICST VCO settings for the Integrator/CP
- * @vco: ICST VCO parameters to update with hardware status
- */
-static struct icst_vco cp_auxvco_get(void)
-{
-	u32 val;
-	struct icst_vco vco;
-
-	val = readl(CM_AUXOSC);
-	vco.v = val & 0x1ff;
-	vco.r = (val >> 9) & 0x7f;
-	vco.s = (val >> 16) & 03;
-	return vco;
-}
-
-/**
- * cp_auxvco_set() - commit changes to Integrator/CP ICST VCO
- * @vco: ICST VCO parameters to commit
- */
-static void cp_auxvco_set(struct icst_vco vco)
-{
-	u32 val;
-
-	val = readl(CM_AUXOSC) & ~0x7ffff;
-	val |= vco.v | (vco.r << 9) | (vco.s << 16);
-
-	/* This magic unlocks the CM VCO so it can be controlled */
-	writel(0xa05f, CM_LOCK);
-	writel(val, CM_AUXOSC);
-	/* This locks the CM again */
-	writel(0, CM_LOCK);
-}
 
 static const struct icst_params cp_auxvco_params = {
 	.ref		= 24000000,
···
 
 static const struct clk_icst_desc __initdata cp_icst_desc = {
 	.params = &cp_auxvco_params,
-	.getvco = cp_auxvco_get,
-	.setvco = cp_auxvco_set,
+	.vco_offset = 0x1c,
+	.lock_offset = INTEGRATOR_HDR_LOCK_OFFSET,
 };
 
 /*
···
 	clk_register_clkdev(clk, NULL, "sp804");
 
 	/* ICST VCO clock used on the Integrator/CP CLCD */
-	clk = icst_clk_register(NULL, &cp_icst_desc);
+	clk = icst_clk_register(NULL, &cp_icst_desc,
+				__io_address(INTEGRATOR_HDR_BASE));
 	clk_register_clkdev(clk, NULL, "clcd");
 }

drivers/clk/versatile/clk-realview.c

···
  * Implementation of the ARM RealView clock trees.
  */
 
-static void __iomem *sys_lock;
-static void __iomem *sys_vcoreg;
-
-/**
- * realview_oscvco_get() - get ICST OSC settings for the RealView
- */
-static struct icst_vco realview_oscvco_get(void)
-{
-	u32 val;
-	struct icst_vco vco;
-
-	val = readl(sys_vcoreg);
-	vco.v = val & 0x1ff;
-	vco.r = (val >> 9) & 0x7f;
-	vco.s = (val >> 16) & 03;
-	return vco;
-}
-
-static void realview_oscvco_set(struct icst_vco vco)
-{
-	u32 val;
-
-	val = readl(sys_vcoreg) & ~0x7ffff;
-	val |= vco.v | (vco.r << 9) | (vco.s << 16);
-
-	/* This magic unlocks the CM VCO so it can be controlled */
-	writel(0xa05f, sys_lock);
-	writel(val, sys_vcoreg);
-	/* This locks the CM again */
-	writel(0, sys_lock);
-}
-
 static const struct icst_params realview_oscvco_params = {
 	.ref		= 24000000,
 	.vco_max	= ICST307_VCO_MAX,
···
 	.idx2s		= icst307_idx2s,
 };
 
-static const struct clk_icst_desc __initdata realview_icst_desc = {
+static const struct clk_icst_desc __initdata realview_osc0_desc = {
 	.params = &realview_oscvco_params,
-	.getvco = realview_oscvco_get,
-	.setvco = realview_oscvco_set,
+	.vco_offset = REALVIEW_SYS_OSC0_OFFSET,
+	.lock_offset = REALVIEW_SYS_LOCK_OFFSET,
+};
+
+static const struct clk_icst_desc __initdata realview_osc4_desc = {
+	.params = &realview_oscvco_params,
+	.vco_offset = REALVIEW_SYS_OSC4_OFFSET,
+	.lock_offset = REALVIEW_SYS_LOCK_OFFSET,
 };
 
 /*
···
 void __init realview_clk_init(void __iomem *sysbase, bool is_pb1176)
 {
 	struct clk *clk;
-
-	sys_lock = sysbase + REALVIEW_SYS_LOCK_OFFSET;
-	if (is_pb1176)
-		sys_vcoreg = sysbase + REALVIEW_SYS_OSC0_OFFSET;
-	else
-		sys_vcoreg = sysbase + REALVIEW_SYS_OSC4_OFFSET;
-
 
 	/* APB clock dummy */
 	clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT, 0);
···
 	clk_register_clkdev(clk, NULL, "sp804");
 
 	/* ICST VCO clock */
-	clk = icst_clk_register(NULL, &realview_icst_desc);
+	if (is_pb1176)
+		clk = icst_clk_register(NULL, &realview_osc0_desc, sysbase);
+	else
+		clk = icst_clk_register(NULL, &realview_osc4_desc, sysbase);
+
 	clk_register_clkdev(clk, NULL, "dev:clcd");
 	clk_register_clkdev(clk, NULL, "issp:clcd");
 }