[PATCH 1/5] arm: sa1100: add cpu clock
Dmitry Eremin-Solenikov
dbaryshkov at gmail.com
Mon Nov 11 22:32:08 EST 2013
Both SA1100 framebuffer and PCMCIA drivers require knowledge of cpu
frequency to correctly program timings. Currently they receive timing
information by calling cpufreq_get(0). However if cpu frequency driver
is not enabled (e.g. due to unsupported DRAM chip/board on sa1110)
cpufreq_get(0) returns 0, causing incorrect timings to be programmed.
Add cpu clock returning cpu frequency, to be used by sa11x0 fb and
pcmcia drivers.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov at gmail.com>
---
arch/arm/mach-sa1100/clock.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c
index 172ebd0..abf1dc1 100644
--- a/arch/arm/mach-sa1100/clock.c
+++ b/arch/arm/mach-sa1100/clock.c
@@ -15,10 +15,12 @@
#include <linux/clkdev.h>
#include <mach/hardware.h>
+#include <mach/generic.h>
struct clkops {
void (*enable)(struct clk *);
void (*disable)(struct clk *);
+ unsigned long (*get_rate)(struct clk *);
};
struct clk {
@@ -51,6 +53,19 @@ static void clk_gpio27_disable(struct clk *clk)
GAFR &= ~GPIO_32_768kHz;
}
+static void clk_cpu_enable(struct clk *clk)
+{
+}
+
+static void clk_cpu_disable(struct clk *clk)
+{
+}
+
+static unsigned long clk_cpu_get_rate(struct clk *clk)
+{
+ return sa11x0_getspeed(0) * 1000;
+}
+
int clk_enable(struct clk *clk)
{
unsigned long flags;
@@ -80,16 +95,35 @@ void clk_disable(struct clk *clk)
}
EXPORT_SYMBOL(clk_disable);
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (clk && clk->ops && clk->ops->get_rate)
+ return clk->ops->get_rate(clk);
+ else
+ return 0;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
const struct clkops clk_gpio27_ops = {
.enable = clk_gpio27_enable,
.disable = clk_gpio27_disable,
};
+const struct clkops clk_cpu_ops = {
+ .enable = clk_cpu_enable,
+ .disable = clk_cpu_disable,
+ .get_rate = clk_cpu_get_rate,
+};
+
static DEFINE_CLK(gpio27, &clk_gpio27_ops);
+static DEFINE_CLK(cpu, &clk_cpu_ops);
+
static struct clk_lookup sa11xx_clkregs[] = {
CLKDEV_INIT("sa1111.0", NULL, &clk_gpio27),
CLKDEV_INIT("sa1100-rtc", NULL, NULL),
+ CLKDEV_INIT("sa11x0-fb", NULL, &clk_cpu),
+ CLKDEV_INIT("sa11x0-pcmcia", NULL, &clk_cpu),
};
static int __init sa11xx_clk_init(void)
--
1.8.4.2
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