diff options
Diffstat (limited to 'target/linux/ramips/patches-3.18/0021-MIPS-ralink-add-cpu-frequency-scaling.patch')
| -rw-r--r-- | target/linux/ramips/patches-3.18/0021-MIPS-ralink-add-cpu-frequency-scaling.patch | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-3.18/0021-MIPS-ralink-add-cpu-frequency-scaling.patch b/target/linux/ramips/patches-3.18/0021-MIPS-ralink-add-cpu-frequency-scaling.patch new file mode 100644 index 0000000..0e567cb --- /dev/null +++ b/target/linux/ramips/patches-3.18/0021-MIPS-ralink-add-cpu-frequency-scaling.patch @@ -0,0 +1,95 @@ +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); |