You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
95 lines
2.7 KiB
95 lines
2.7 KiB
From e76ecd496c9b074ab21b17f12494d823a407e89a Mon Sep 17 00:00:00 2001
|
|
From: John Crispin <blogic@openwrt.org>
|
|
Date: Sun, 28 Jul 2013 16:26:41 +0200
|
|
Subject: [PATCH 21/57] MIPS: ralink: add cpu frequency scaling
|
|
|
|
This feature will break udelay() and cause the delay loop to have longer delays
|
|
when the frequency is scaled causing a performance hit.
|
|
|
|
Signed-off-by: John Crispin <blogic@openwrt.org>
|
|
---
|
|
arch/mips/ralink/cevt-rt3352.c | 36 ++++++++++++++++++++++++++++++++++++
|
|
1 file changed, 36 insertions(+)
|
|
|
|
--- a/arch/mips/ralink/cevt-rt3352.c
|
|
+++ b/arch/mips/ralink/cevt-rt3352.c
|
|
@@ -29,6 +29,10 @@
|
|
/* enable the counter */
|
|
#define CFG_CNT_EN 0x1
|
|
|
|
+/* mt7620 frequency scaling defines */
|
|
+#define CLK_LUT_CFG 0x40
|
|
+#define SLEEP_EN BIT(31)
|
|
+
|
|
struct systick_device {
|
|
void __iomem *membase;
|
|
struct clock_event_device dev;
|
|
@@ -36,6 +40,8 @@ struct systick_device {
|
|
int freq_scale;
|
|
};
|
|
|
|
+static void (*systick_freq_scaling)(struct systick_device *sdev, int status);
|
|
+
|
|
static void systick_set_clock_mode(enum clock_event_mode mode,
|
|
struct clock_event_device *evt);
|
|
|
|
@@ -87,6 +93,21 @@ static struct irqaction systick_irqactio
|
|
.dev_id = &systick.dev,
|
|
};
|
|
|
|
+static inline void mt7620_freq_scaling(struct systick_device *sdev, int status)
|
|
+{
|
|
+ if (sdev->freq_scale == status)
|
|
+ return;
|
|
+
|
|
+ sdev->freq_scale = status;
|
|
+
|
|
+ pr_info("%s: %s autosleep mode\n", systick.dev.name,
|
|
+ (status) ? ("enable") : ("disable"));
|
|
+ if (status)
|
|
+ rt_sysc_w32(rt_sysc_r32(CLK_LUT_CFG) | SLEEP_EN, CLK_LUT_CFG);
|
|
+ else
|
|
+ rt_sysc_w32(rt_sysc_r32(CLK_LUT_CFG) & ~SLEEP_EN, CLK_LUT_CFG);
|
|
+}
|
|
+
|
|
static void systick_set_clock_mode(enum clock_event_mode mode,
|
|
struct clock_event_device *evt)
|
|
{
|
|
@@ -101,9 +122,13 @@ static void systick_set_clock_mode(enum
|
|
sdev->irq_requested = 1;
|
|
iowrite32(CFG_EXT_STK_EN | CFG_CNT_EN,
|
|
systick.membase + SYSTICK_CONFIG);
|
|
+ if (systick_freq_scaling)
|
|
+ systick_freq_scaling(sdev, 1);
|
|
break;
|
|
|
|
case CLOCK_EVT_MODE_SHUTDOWN:
|
|
+ if (systick_freq_scaling)
|
|
+ systick_freq_scaling(sdev, 0);
|
|
if (sdev->irq_requested)
|
|
free_irq(systick.dev.irq, &systick_irqaction);
|
|
sdev->irq_requested = 0;
|
|
@@ -116,12 +141,23 @@ static void systick_set_clock_mode(enum
|
|
}
|
|
}
|
|
|
|
+static const struct of_device_id systick_match[] = {
|
|
+ { .compatible = "ralink,mt7620-systick", .data = mt7620_freq_scaling},
|
|
+ {},
|
|
+};
|
|
+
|
|
static void __init ralink_systick_init(struct device_node *np)
|
|
{
|
|
+ const struct of_device_id *match;
|
|
+
|
|
systick.membase = of_iomap(np, 0);
|
|
if (!systick.membase)
|
|
return;
|
|
|
|
+ match = of_match_node(systick_match, np);
|
|
+ if (match)
|
|
+ systick_freq_scaling = match->data;
|
|
+
|
|
systick_irqaction.name = np->name;
|
|
systick.dev.name = np->name;
|
|
clockevents_calc_mult_shift(&systick.dev, SYSTICK_FREQ, 60);
|
|
|