ARM: 6145/1: ux500 MTU clockrate correction

This adjusts the clockrate for the MTU timer. On the different
UX500 variants this rate is different. The platform can also have
been set up at hardware initialization, bootloader or early init
for different clock speeds. To have the clock framework available
early so the timers can use them, the clock initialization for
Nomadik and ux500 is moved to IRQ init time. A custom per-clock
callback is added to handle special cases like this.

This solves a user-visible bug: without this patch the current
UX500 platforms will not be synchronized to wall-clock time and
the platform will drift in time.

Acked-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/arm/mach-ux500/clock.h b/arch/arm/mach-ux500/clock.h
index e4f99b65026f..a05802501527 100644
--- a/arch/arm/mach-ux500/clock.h
+++ b/arch/arm/mach-ux500/clock.h
@@ -28,6 +28,9 @@ struct clkops {
  * @ops:                pointer to clkops struct used to control this clock
  * @name:               name, for debugging
  * @enabled:            refcount. positive if enabled, zero if disabled
+ * @get_rate:           custom callback for getting the clock rate
+ * @data:               custom per-clock data for example for the get_rate
+ *                      callback
  * @rate:               fixed rate for clocks which don't implement
  *                      ops->getrate
  * @prcmu_cg_off:       address offset of the combined enable/disable register
@@ -67,6 +70,8 @@ struct clk {
         const struct clkops     *ops;
         const char              *name;
         unsigned int            enabled;
+        unsigned long           (*get_rate)(struct clk *);
+        void                    *data;
 
         unsigned long           rate;
         struct list_head        list;
@@ -117,9 +122,26 @@ struct clk clk_##_name = {						\
                 .parent_periph  = _kernclk                              \
         }
 
+#define DEFINE_PRCC_CLK_CUSTOM(_pclust, _name, _bus_en, _kernel_en, _kernclk, _callback, _data) \
+struct clk clk_##_name = {                                              \
+                .name           = #_name,                               \
+                .ops            = &clk_prcc_ops,                        \
+                .cluster        = _pclust,                              \
+                .prcc_bus       = _bus_en,                              \
+                .prcc_kernel    = _kernel_en,                           \
+                .parent_cluster = &clk_per##_pclust##clk,               \
+                .parent_periph  = _kernclk,                             \
+                .get_rate       = _callback,                            \
+                .data           = (void *) _data                        \
+        }
+
+
 #define CLK(_clk, _devname, _conname)                   \
         {                                               \
                 .clk    = &clk_##_clk,                  \
                 .dev_id = _devname,                     \
                 .con_id = _conname,                     \
         }
+
+int __init clk_db8500_ed_fixup(void);
+int __init clk_init(void);