target/linux/ramips/patches-3.8/0079-clocksource-MIPS-ralink-add-support-for-systick-time.patch

   1 From 4f3ae2a7ee1b1c9b9cab287c828f2ed7b1858495 Mon Sep 17 00:00:00 2001
   2 From: John Crispin <blogic@openwrt.org>
   3 Date: Thu, 20 Jun 2013 19:21:52 +0200
   4 Subject: [PATCH 79/79] clocksource: MIPS: ralink: add support for systick
   5  timer found on newer ralink SoC
   6
   7 Signed-off-by: John Crispin <blogic@openwrt.org
   8 ---
   9  arch/mips/pci/Makefile.rej        |   10 +++
  10  arch/mips/ralink/Kconfig          |    2 +
  11  arch/mips/ralink/Kconfig.rej      |   10 +++
  12  arch/mips/ralink/clk.c            |    1 +
  13  drivers/clocksource/Kconfig       |    6 ++
  14  drivers/clocksource/Makefile      |    1 +
  15  drivers/clocksource/cevt-rt3352.c |  162 +++++++++++++++++++++++++++++++++++++
  16  7 files changed, 192 insertions(+)
  17  create mode 100644 arch/mips/pci/Makefile.rej
  18  create mode 100644 arch/mips/ralink/Kconfig.rej
  19  create mode 100644 drivers/clocksource/cevt-rt3352.c
  20
  21 diff --git a/arch/mips/pci/Makefile.rej b/arch/mips/pci/Makefile.rej
  22 new file mode 100644
  23 index 0000000..c5761e8
  24 --- /dev/null
  25 +++ b/arch/mips/pci/Makefile.rej
  26 @@ -0,0 +1,10 @@
  27 +--- arch/mips/pci/Makefile
  28 ++++ arch/mips/pci/Makefile
  29 +@@ -43,6 +43,7 @@
  30 + obj-$(CONFIG_PCI_LANTIQ)      += pci-lantiq.o ops-lantiq.o
  31 + obj-$(CONFIG_SOC_RT2880)      += pci-rt2880.o
  32 + obj-$(CONFIG_SOC_RT3883)      += pci-rt3883.o
  33 ++obj-$(CONFIG_SOC_MT7620)      += pci-mt7620a.o
  34 + obj-$(CONFIG_TANBAC_TB0219)   += fixup-tb0219.o
  35 + obj-$(CONFIG_TANBAC_TB0226)   += fixup-tb0226.o
  36 + obj-$(CONFIG_TANBAC_TB0287)   += fixup-tb0287.o
  37 diff --git a/arch/mips/ralink/Kconfig b/arch/mips/ralink/Kconfig
  38 index f89fdf8..c8d5b6c 100644
  39 --- a/arch/mips/ralink/Kconfig
  40 +++ b/arch/mips/ralink/Kconfig
  41 @@ -15,6 +15,7 @@ choice
  42                 select USB_ARCH_HAS_HCD
  43                 select USB_ARCH_HAS_OHCI
  44                 select USB_ARCH_HAS_EHCI
  45 +               select CLKEVT_RT3352
  46
  47         config SOC_RT3883
  48                 bool "RT3883"
  49 @@ -24,6 +25,7 @@ choice
  50
  51         config SOC_MT7620
  52                 bool "MT7620"
  53 +               select CLKEVT_RT3352
  54                 select HW_HAS_PCI
  55
  56  endchoice
  57 diff --git a/arch/mips/ralink/Kconfig.rej b/arch/mips/ralink/Kconfig.rej
  58 new file mode 100644
  59 index 0000000..d3a804f
  60 --- /dev/null
  61 +++ b/arch/mips/ralink/Kconfig.rej
  62 @@ -0,0 +1,10 @@
  63 +--- arch/mips/ralink/Kconfig
  64 ++++ arch/mips/ralink/Kconfig
  65 +@@ -23,6 +24,7 @@
  66 +
  67 +       config SOC_MT7620
  68 +               bool "MT7620"
  69 ++              select CLKEVT_RT3352
  70 +
  71 + endchoice
  72 +
  73 diff --git a/arch/mips/ralink/clk.c b/arch/mips/ralink/clk.c
  74 index 8dfa22f..bba0cdf 100644
  75 --- a/arch/mips/ralink/clk.c
  76 +++ b/arch/mips/ralink/clk.c
  77 @@ -69,4 +69,5 @@ void __init plat_time_init(void)
  78         pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000);
  79         mips_hpt_frequency = clk_get_rate(clk) / 2;
  80         clk_put(clk);
  81 +       clocksource_of_init();
  82  }
  83 diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
  84 index a32b7a9..90bed1a 100644
  85 --- a/drivers/clocksource/Kconfig
  86 +++ b/drivers/clocksource/Kconfig
  87 @@ -7,6 +7,12 @@ config CLKSRC_I8253
  88  config CLKEVT_I8253
  89         bool
  90
  91 +config CLKEVT_RT3352
  92 +       bool
  93 +       depends on MIPS && RALINK
  94 +       select CLKSRC_OF
  95 +       select CLKSRC_MMIO
  96 +
  97  config I8253_LOCK
  98         bool
  99
 100 diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
 101 index a33f792..5031f82 100644
 102 --- a/drivers/clocksource/Makefile
 103 +++ b/drivers/clocksource/Makefile
 104 @@ -10,6 +10,7 @@ obj-$(CONFIG_SH_TIMER_TMU)    += sh_tmu.o
 105  obj-$(CONFIG_EM_TIMER_STI)     += em_sti.o
 106  obj-$(CONFIG_CLKBLD_I8253)     += i8253.o
 107  obj-$(CONFIG_CLKSRC_MMIO)      += mmio.o
 108 +obj-$(CONFIG_CLKEVT_RT3352)    += cevt-rt3352.o
 109  obj-$(CONFIG_DW_APB_TIMER)     += dw_apb_timer.o
 110  obj-$(CONFIG_DW_APB_TIMER_OF)  += dw_apb_timer_of.o
 111  obj-$(CONFIG_CLKSRC_NOMADIK_MTU)       += nomadik-mtu.o
 112 diff --git a/drivers/clocksource/cevt-rt3352.c b/drivers/clocksource/cevt-rt3352.c
 113 new file mode 100644
 114 index 0000000..bd50edd
 115 --- /dev/null
 116 +++ b/drivers/clocksource/cevt-rt3352.c
 117 @@ -0,0 +1,162 @@
 118 +/*
 119 + * This file is subject to the terms and conditions of the GNU General Public
 120 + * License.  See the file "COPYING" in the main directory of this archive
 121 + * for more details.
 122 + *
 123 + * Copyright (C) 2013 by John Crispin <blogic@openwrt.org>
 124 + */
 125 +
 126 +#include <linux/clockchips.h>
 127 +#include <linux/clocksource.h>
 128 +#include <linux/interrupt.h>
 129 +#include <linux/reset.h>
 130 +#include <linux/init.h>
 131 +#include <linux/of.h>
 132 +#include <linux/of_irq.h>
 133 +#include <linux/of_address.h>
 134 +
 135 +#include <asm/mach-ralink/ralink_regs.h>
 136 +#include <asm/time.h>
 137 +
 138 +#define SYSTICK_FREQ   (50 * 1000)
 139 +
 140 +#define SYSTICK_CONFIG 0x00
 141 +#define SYSTICK_COMPARE        0x04
 142 +#define SYSTICK_COUNT  0x08
 143 +
 144 +/* route systick irq to mips irq 7 instead of the r4k-timer */
 145 +#define CFG_EXT_STK_EN 0x2
 146 +/* enable the counter */
 147 +#define CFG_CNT_EN     0x1
 148 +
 149 +struct systick_device {
 150 +       void __iomem *membase;
 151 +       struct clock_event_device dev;
 152 +       int irq_requested;
 153 +       int freq_scale;
 154 +};
 155 +
 156 +static void systick_set_clock_mode(enum clock_event_mode mode,
 157 +                               struct clock_event_device *evt);
 158 +
 159 +static int systick_next_event(unsigned long delta,
 160 +                               struct clock_event_device *evt)
 161 +{
 162 +       struct systick_device *sdev = container_of(evt, struct systick_device, dev);
 163 +       u32 count;
 164 +
 165 +       count = ioread32(sdev->membase + SYSTICK_COUNT);
 166 +       count = (count + delta) % SYSTICK_FREQ;
 167 +       iowrite32(count + delta, sdev->membase + SYSTICK_COMPARE);
 168 +
 169 +       return 0;
 170 +}
 171 +
 172 +static void systick_event_handler(struct clock_event_device *dev)
 173 +{
 174 +       /* noting to do here */
 175 +}
 176 +
 177 +static irqreturn_t systick_interrupt(int irq, void *dev_id)
 178 +{
 179 +       struct clock_event_device *dev = (struct clock_event_device *) dev_id;
 180 +
 181 +       dev->event_handler(dev);
 182 +
 183 +       return IRQ_HANDLED;
 184 +}
 185 +
 186 +static struct systick_device systick = {
 187 +       .dev = {
 188 +               /* cevt-r4k uses 300, make sure systick gets used if available */
 189 +               .rating         = 310,
 190 +               .features       = CLOCK_EVT_FEAT_ONESHOT,
 191 +               .set_next_event = systick_next_event,
 192 +               .set_mode       = systick_set_clock_mode,
 193 +               .event_handler  = systick_event_handler,
 194 +       },
 195 +};
 196 +
 197 +static struct irqaction systick_irqaction = {
 198 +       .handler = systick_interrupt,
 199 +       .flags = IRQF_PERCPU | IRQF_TIMER,
 200 +       .dev_id = &systick.dev,
 201 +};
 202 +
 203 +/* ugly hack */
 204 +#ifdef CONFIG_SOC_MT7620
 205 +
 206 +#define CLK_LUT_CFG    0x40
 207 +#define SLEEP_EN       BIT(31)
 208 +
 209 +static inline void mt7620_freq_scaling(struct systick_device *sdev, int status)
 210 +{
 211 +       if (sdev->freq_scale == status)
 212 +               return;
 213 +
 214 +       sdev->freq_scale = status;
 215 +
 216 +       pr_info("%s: %s autosleep mode\n", systick.dev.name, (status) ? ("enable") : ("disable"));
 217 +       if (status)
 218 +               rt_sysc_w32(rt_sysc_r32(CLK_LUT_CFG) | SLEEP_EN, CLK_LUT_CFG);
 219 +       else
 220 +               rt_sysc_w32(rt_sysc_r32(CLK_LUT_CFG) & ~SLEEP_EN, CLK_LUT_CFG);
 221 +}
 222 +#else
 223 +static inline void mt7620_freq_scaling(struct systick_device *sdev, int status) {}
 224 +#endif
 225 +
 226 +static void systick_set_clock_mode(enum clock_event_mode mode,
 227 +                               struct clock_event_device *evt)
 228 +{
 229 +       struct systick_device *sdev = container_of(evt, struct systick_device, dev);
 230 +
 231 +       switch (mode) {
 232 +       case CLOCK_EVT_MODE_ONESHOT:
 233 +               if (!sdev->irq_requested)
 234 +                       setup_irq(systick.dev.irq, &systick_irqaction);
 235 +               mt7620_freq_scaling(sdev, 1);
 236 +               sdev->irq_requested = 1;
 237 +               iowrite32(CFG_EXT_STK_EN | CFG_CNT_EN, systick.membase + SYSTICK_CONFIG);
 238 +               break;
 239 +
 240 +       case CLOCK_EVT_MODE_SHUTDOWN:
 241 +               if (sdev->irq_requested)
 242 +                       free_irq(systick.dev.irq, &systick_irqaction);
 243 +               mt7620_freq_scaling(sdev, 0);
 244 +               sdev->irq_requested = 0;
 245 +               iowrite32(0, systick.membase + SYSTICK_CONFIG);
 246 +               break;
 247 +
 248 +       default:
 249 +               pr_err("%s: Unhandeled mips clock_mode\n", systick.dev.name);
 250 +               break;
 251 +       }
 252 +}
 253 +
 254 +static void __init ralink_systick_init(struct device_node *np)
 255 +{
 256 +       systick.membase = of_iomap(np, 0);
 257 +       if (!systick.membase) {
 258 +               pr_err("%s: of_iomap failed", np->name);
 259 +               return;
 260 +       }
 261 +
 262 +       clocksource_mmio_init(systick.membase + SYSTICK_COUNT, np->name,
 263 +                       SYSTICK_FREQ, 301, 16, clocksource_mmio_readl_up);
 264 +
 265 +       systick_irqaction.name = np->name;
 266 +       systick.dev.name = np->name;
 267 +       clockevent_set_clock(&systick.dev, SYSTICK_FREQ);
 268 +       systick.dev.max_delta_ns = clockevent_delta2ns(0x7fff, &systick.dev);
 269 +       systick.dev.min_delta_ns = clockevent_delta2ns(0x3, &systick.dev);
 270 +       systick.dev.irq = irq_of_parse_and_map(np, 0);
 271 +       if (!systick.dev.irq)
 272 +               panic("%s: request_irq failed", np->name);
 273 +
 274 +       clockevents_register_device(&systick.dev);
 275 +
 276 +       pr_info("%s: runing - mult: %d, shift: %d\n", np->name, systick.dev.mult, systick.dev.shift);
 277 +}
 278 +
 279 +CLOCKSOURCE_OF_DECLARE(systick, "ralink,cevt-systick", ralink_systick_init);
 280 --
 281 1.7.10.4
 282