ARM: OMAP2+: PRM: add support for initializing PRCM clock modules fro…

…m DT

This patch provides top level functionality for the DT clock initialization.
Clock tree is initialized hierarchically starting from IP modules (CM/PRM/PRCM)
going down towards individual clock nodes, and finally initializing
clockdomains once all the clocks are ready.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

arch/arm/mach-omap2/prm.h

@@ -18,6 +18,7 @@
 # ifndef __ASSEMBLER__
 extern void __iomem *prm_base;
 extern void omap2_set_globals_prm(void __iomem *prm);
+int of_prcm_init(void);
 # endif
 
 

arch/arm/mach-omap2/prm_common.c

@@ -23,13 +23,18 @@
 #include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk-provider.h>
+#include <linux/clk/ti.h>
 
 #include "soc.h"
 #include "prm2xxx_3xxx.h"
 #include "prm2xxx.h"
 #include "prm3xxx.h"
 #include "prm44xx.h"
 #include "common.h"
+#include "clock.h"
 
 /*
  * OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs
@@ -464,3 +469,64 @@ int prm_unregister(struct prm_ll_data *pld)
 
 	return 0;
 }
+
+static struct of_device_id omap_prcm_dt_match_table[] = {
+	{ .compatible = "ti,am3-prcm" },
+	{ .compatible = "ti,am3-scrm" },
+	{ .compatible = "ti,am4-prcm" },
+	{ .compatible = "ti,am4-scrm" },
+	{ .compatible = "ti,omap3-prm" },
+	{ .compatible = "ti,omap3-cm" },
+	{ .compatible = "ti,omap3-scrm" },
+	{ .compatible = "ti,omap4-cm1" },
+	{ .compatible = "ti,omap4-prm" },
+	{ .compatible = "ti,omap4-cm2" },
+	{ .compatible = "ti,omap4-scrm" },
+	{ .compatible = "ti,omap5-prm" },
+	{ .compatible = "ti,omap5-cm-core-aon" },
+	{ .compatible = "ti,omap5-scrm" },
+	{ .compatible = "ti,omap5-cm-core" },
+	{ .compatible = "ti,dra7-prm" },
+	{ .compatible = "ti,dra7-cm-core-aon" },
+	{ .compatible = "ti,dra7-cm-core" },
+	{ }
+};
+
+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,
+};
+
+int __init of_prcm_init(void)
+{
+	struct device_node *np;
+	void __iomem *mem;
+	int memmap_index = 0;
+
+	ti_clk_ll_ops = &omap_clk_ll_ops;
+
+	for_each_matching_node(np, omap_prcm_dt_match_table) {
+		mem = of_iomap(np, 0);
+		clk_memmaps[memmap_index] = mem;
+		ti_dt_clk_init_provider(np, memmap_index);
+		memmap_index++;
+	}
+
+	ti_dt_clockdomains_setup();
+
+	return 0;
+}