ARM: integrator: read counter using syscon/regmap

Look up the core module base address from the device tree and
register a sched_clock() using the regmap to the core module
on the Integrator/CP.

MFD_SYSCON is selected by the arch so it is always available.

This further makes it possible to remove one more static map.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/arch/arm/mach-integrator/integrator_cp.c b/arch/arm/mach-integrator/integrator_cp.c
index 8db029fa60522aee6804411795398187bd7d1f90..772a7cf2010e78a7f3c6aa32f3ae49fe263355a4 100644 (file)
--- a/arch/arm/mach-integrator/integrator_cp.c
+++ b/arch/arm/mach-integrator/integrator_cp.c
@@ -15,6 +15,8 @@
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/sched_clock.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
@@ -23,12 +25,15 @@
 #include "cm.h"
 #include "common.h"
 
+/* Base address to the core module header */
+static struct regmap *cm_map;
 /* Base address to the CP controller */
 static void __iomem *intcp_con_base;
 
+#define CM_COUNTER_OFFSET 0x28
+
 /*
  * Logical      Physical
- * f1000000    10000000        Core module registers
  * f1400000    14000000        Interrupt controller
  * f1600000    16000000        UART 0
  * fca00000    ca000000        SIC
@@ -36,11 +41,6 @@ static void __iomem *intcp_con_base;
 
 static struct map_desc intcp_io_desc[] __initdata __maybe_unused = {
        {
-               .virtual        = IO_ADDRESS(INTEGRATOR_HDR_BASE),
-               .pfn            = __phys_to_pfn(INTEGRATOR_HDR_BASE),
-               .length         = SZ_4K,
-               .type           = MT_DEVICE
-       }, {
                .virtual        = IO_ADDRESS(INTEGRATOR_IC_BASE),
                .pfn            = __phys_to_pfn(INTEGRATOR_IC_BASE),
                .length         = SZ_4K,
@@ -84,15 +84,20 @@ static struct mmci_platform_data mmc_data = {
        .gpio_cd        = -1,
 };
 
-#define REFCOUNTER (__io_address(INTEGRATOR_HDR_BASE) + 0x28)
-
 static u64 notrace intcp_read_sched_clock(void)
 {
-       return readl(REFCOUNTER);
+       unsigned int val;
+
+       /* MMIO so discard return code */
+       regmap_read(cm_map, CM_COUNTER_OFFSET, &val);
+       return val;
 }
 
 static void __init intcp_init_early(void)
 {
+       cm_map = syscon_regmap_lookup_by_compatible("arm,core-module-integrator");
+       if (IS_ERR(cm_map))
+               return;
        sched_clock_register(intcp_read_sched_clock, 32, 24000000);
 }