Xilinx Zynq SLCR changes

index 1db2a5ca..bf6717f 100644
@@ -64,6 +64,8 @@ static void __init zynq_init_machine(void)
 static void __init zynq_timer_init(void)
 {
 	zynq_slcr_init();
+
+	zynq_clock_init(zynq_slcr_base);
 	clocksource_of_init();
 }
 

index 1836d5a..59ad09f 100644
@@ -106,8 +106,6 @@ int __init zynq_slcr_init(void)
 
 	pr_info("%s mapped to %p\n", np->name, zynq_slcr_base);
 
-	zynq_clock_init(zynq_slcr_base);
-
 	of_node_put(np);
 
 	return 0;

index bf6717f..38401cf 100644
@@ -59,11 +59,13 @@ static void __init zynq_init_machine(void)
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 
 	platform_device_register(&zynq_cpuidle_device);
+
+	zynq_slcr_init();
 }
 
 static void __init zynq_timer_init(void)
 {
-	zynq_slcr_init();
+	zynq_early_slcr_init();
 
 	zynq_clock_init(zynq_slcr_base);
 	clocksource_of_init();

index c22c92c..1548b85 100644
@@ -20,6 +20,7 @@
 void zynq_secondary_startup(void);
 
 extern int zynq_slcr_init(void);
+extern int zynq_early_slcr_init(void);
 extern void zynq_slcr_system_reset(void);
 extern void zynq_slcr_cpu_stop(int cpu);
 extern void zynq_slcr_cpu_start(int cpu);

index 59ad09f..9746de7 100644
@@ -15,7 +15,9 @@
  */
 
 #include <linux/io.h>
+#include <linux/mfd/syscon.h>
 #include <linux/of_address.h>
+#include <linux/regmap.h>
 #include <linux/clk/zynq.h>
 #include "common.h"
 

@@ -30,6 +32,7 @@
 #define SLCR_A9_CPU_RST			0x1
 
 void __iomem *zynq_slcr_base;
+static struct regmap *zynq_slcr_regmap;
 
 /**
  * zynq_slcr_system_reset - Reset the entire system.

@@ -87,6 +90,23 @@ void zynq_slcr_cpu_stop(int cpu)
  */
 int __init zynq_slcr_init(void)
 {
+	zynq_slcr_regmap = syscon_regmap_lookup_by_compatible("xlnx,zynq-slcr");
+	if (IS_ERR(zynq_slcr_regmap)) {
+		pr_err("%s: failed to find zynq-slcr\n", __func__);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+/**
+ * zynq_early_slcr_init
+ * Returns 0 on success, negative errno otherwise.
+ *
+ * Called very early during boot from platform code to unlock SLCR.
+ */
+int __init zynq_early_slcr_init(void)
+{
 	struct device_node *np;
 
 	np = of_find_compatible_node(NULL, NULL, "xlnx,zynq-slcr");

index 9746de7..2891dcf 100644
@@ -121,6 +121,8 @@ int __init zynq_early_slcr_init(void)
 		BUG();
 	}
 
+	np->data = (__force void *)zynq_slcr_base;
+
 	/* unlock the SLCR so that registers can be changed */
 	writel(SLCR_UNLOCK_MAGIC, zynq_slcr_base + SLCR_UNLOCK_OFFSET);
 

index 38401cf..93ea19b 100644
@@ -67,7 +67,7 @@ static void __init zynq_timer_init(void)
 {
 	zynq_early_slcr_init();
 
-	zynq_clock_init(zynq_slcr_base);
+	zynq_clock_init();
 	clocksource_of_init();
 }
 

105 lines not on this page · raw message

index e062d31..7a5633b 100644
@@ -22,7 +22,7 @@
 
 #include <linux/spinlock.h>
 
-void zynq_clock_init(void __iomem *slcr);
+void zynq_clock_init(void);
 
 struct clk *clk_register_zynq_pll(const char *name, const char *parent,
 		void __iomem *pll_ctrl, void __iomem *pll_status, u8 lock_index,

index 1548b85..b097844 100644
@@ -34,7 +34,6 @@ extern int zynq_cpun_start(u32 address, int cpu);
 extern struct smp_operations zynq_smp_ops __initdata;
 #endif
 
-extern void __iomem *zynq_slcr_base;
 extern void __iomem *zynq_scu_base;
 
 /* Hotplug */

index 2891dcf..a679dff 100644
@@ -31,7 +31,7 @@
 #define SLCR_A9_CPU_CLKSTOP		0x10
 #define SLCR_A9_CPU_RST			0x1
 
-void __iomem *zynq_slcr_base;
+static void __iomem *zynq_slcr_base;
 static struct regmap *zynq_slcr_regmap;
 
 /**

index a679dff..f0f6a69 100644
@@ -35,6 +35,42 @@ static void __iomem *zynq_slcr_base;
 static struct regmap *zynq_slcr_regmap;
 
 /**
+ * zynq_slcr_write - Write to a register in SLCR block
+ *
+ * @val:	Value to write to the register
+ * @offset:	Register offset in SLCR block
+ *
+ * return:	a negative value on error, 0 on success
+ */
+static int zynq_slcr_write(u32 val, u32 offset)
+{
+	if (!zynq_slcr_regmap) {
+		writel(val, zynq_slcr_base + offset);
+		return 0;
+	}
+
+	return regmap_write(zynq_slcr_regmap, offset, val);
+}
+
+/**
+ * zynq_slcr_read - Read a register in SLCR block
+ *
+ * @val:	Pointer to value to be read from SLCR
+ * @offset:	Register offset in SLCR block
+ *
+ * return:	a negative value on error, 0 on success
+ */
+static int zynq_slcr_read(u32 *val, u32 offset)
+{
+	if (zynq_slcr_regmap)
+		return regmap_read(zynq_slcr_regmap, offset, val);
+
+	*val = readl(zynq_slcr_base + offset);
+
+	return 0;
+}
+
+/**
  * zynq_slcr_system_reset - Reset the entire system.
  */
 void zynq_slcr_system_reset(void)

@@ -53,9 +89,9 @@ void zynq_slcr_system_reset(void)
 	 * the FSBL not loading the bitstream after soft-reboot
 	 * This is a temporary solution until we know more.
 	 */
-	reboot = readl(zynq_slcr_base + SLCR_REBOOT_STATUS_OFFSET);
-	writel(reboot & 0xF0FFFFFF, zynq_slcr_base + SLCR_REBOOT_STATUS_OFFSET);
-	writel(1, zynq_slcr_base + SLCR_PS_RST_CTRL_OFFSET);
+	zynq_slcr_read(&reboot, SLCR_REBOOT_STATUS_OFFSET);
+	zynq_slcr_write(reboot & 0xF0FFFFFF, SLCR_REBOOT_STATUS_OFFSET);
+	zynq_slcr_write(1, SLCR_PS_RST_CTRL_OFFSET);
 }
 
 /**

@@ -64,11 +100,13 @@ void zynq_slcr_system_reset(void)
  */
 void zynq_slcr_cpu_start(int cpu)
 {
-	u32 reg = readl(zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET);
+	u32 reg;
+
+	zynq_slcr_read(&reg, SLCR_A9_CPU_RST_CTRL_OFFSET);
 	reg &= ~(SLCR_A9_CPU_RST << cpu);
-	writel(reg, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET);
+	zynq_slcr_write(reg, SLCR_A9_CPU_RST_CTRL_OFFSET);
 	reg &= ~(SLCR_A9_CPU_CLKSTOP << cpu);
-	writel(reg, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET);
+	zynq_slcr_write(reg, SLCR_A9_CPU_RST_CTRL_OFFSET);
 }
 
 /**

@@ -77,9 +115,11 @@ void zynq_slcr_cpu_start(int cpu)
  */
 void zynq_slcr_cpu_stop(int cpu)
 {
-	u32 reg = readl(zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET);
+	u32 reg;
+
+	zynq_slcr_read(&reg, SLCR_A9_CPU_RST_CTRL_OFFSET);
 	reg |= (SLCR_A9_CPU_CLKSTOP | SLCR_A9_CPU_RST) << cpu;
-	writel(reg, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET);
+	zynq_slcr_write(reg, SLCR_A9_CPU_RST_CTRL_OFFSET);
 }
 
 /**

index f0f6a69..c1f1499 100644
@@ -71,6 +71,18 @@ static int zynq_slcr_read(u32 *val, u32 offset)
 }
 
 /**
+ * zynq_slcr_unlock - Unlock SLCR registers
+ *
+ * return:	a negative value on error, 0 on success
+ */
+static inline int zynq_slcr_unlock(void)
+{
+	zynq_slcr_write(SLCR_UNLOCK_MAGIC, SLCR_UNLOCK_OFFSET);
+
+	return 0;
+}
+
+/**
  * zynq_slcr_system_reset - Reset the entire system.
  */
 void zynq_slcr_system_reset(void)

@@ -82,7 +94,7 @@ void zynq_slcr_system_reset(void)
 	 * Note that this seems to require raw i/o
 	 * functions or there's a lockup?
 	 */
-	writel(SLCR_UNLOCK_MAGIC, zynq_slcr_base + SLCR_UNLOCK_OFFSET);
+	zynq_slcr_unlock();
 
 	/*
 	 * Clear 0x0F000000 bits of reboot status register to workaround

@@ -164,7 +176,7 @@ int __init zynq_early_slcr_init(void)
 	np->data = (__force void *)zynq_slcr_base;
 
 	/* unlock the SLCR so that registers can be changed */
-	writel(SLCR_UNLOCK_MAGIC, zynq_slcr_base + SLCR_UNLOCK_OFFSET);
+	zynq_slcr_unlock();
 
 	pr_info("%s mapped to %p\n", np->name, zynq_slcr_base);