target/linux/imx6/patches-3.14/0008-ARM-imx-add-speed-grading-check-for-i.mx6-soc.patch

   1 From c962a0996335fae7f79e64677f47d4784b86f692 Mon Sep 17 00:00:00 2001
   2 From: Anson Huang <b20788@freescale.com>
   3 Date: Wed, 12 Feb 2014 17:57:03 +0800
   4 Subject: [PATCH] ARM: imx: add speed grading check for i.mx6 soc
   5
   6 The fuse map of speed_grading[1:0] defines the max speed
   7 of ARM, see below the definition:
   8
   9 2b'11: 1200000000Hz;
  10 2b'10: 996000000Hz;
  11 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz.
  12 2b'00: 792000000Hz;
  13
  14 Need to remove all illegal setpoints according to fuse
  15 map.
  16
  17 Signed-off-by: Anson Huang <b20788@freescale.com>
  18 Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
  19 ---
  20  arch/arm/mach-imx/mach-imx6q.c | 26 +++++++++++++++++++++++---
  21  1 file changed, 23 insertions(+), 3 deletions(-)
  22
  23 --- a/arch/arm/mach-imx/mach-imx6q.c
  24 +++ b/arch/arm/mach-imx/mach-imx6q.c
  25 @@ -219,8 +219,10 @@ static void __init imx6q_init_machine(vo
  26  #define OCOTP_CFG3                     0x440
  27  #define OCOTP_CFG3_SPEED_SHIFT         16
  28  #define OCOTP_CFG3_SPEED_1P2GHZ                0x3
  29 +#define OCOTP_CFG3_SPEED_996MHZ                0x2
  30 +#define OCOTP_CFG3_SPEED_852MHZ                0x1
  31
  32 -static void __init imx6q_opp_check_1p2ghz(struct device *cpu_dev)
  33 +static void __init imx6q_opp_check_speed_grading(struct device *cpu_dev)
  34  {
  35         struct device_node *np;
  36         void __iomem *base;
  37 @@ -238,11 +240,29 @@ static void __init imx6q_opp_check_1p2gh
  38                 goto put_node;
  39         }
  40
  41 +       /*
  42 +        * SPEED_GRADING[1:0] defines the max speed of ARM:
  43 +        * 2b'11: 1200000000Hz;
  44 +        * 2b'10: 996000000Hz;
  45 +        * 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz.
  46 +        * 2b'00: 792000000Hz;
  47 +        * We need to set the max speed of ARM according to fuse map.
  48 +        */
  49         val = readl_relaxed(base + OCOTP_CFG3);
  50         val >>= OCOTP_CFG3_SPEED_SHIFT;
  51 -       if ((val & 0x3) != OCOTP_CFG3_SPEED_1P2GHZ)
  52 +       val &= 0x3;
  53 +
  54 +       if (val != OCOTP_CFG3_SPEED_1P2GHZ)
  55                 if (dev_pm_opp_disable(cpu_dev, 1200000000))
  56                         pr_warn("failed to disable 1.2 GHz OPP\n");
  57 +       if (val < OCOTP_CFG3_SPEED_996MHZ)
  58 +               if (dev_pm_opp_disable(cpu_dev, 996000000))
  59 +                       pr_warn("failed to disable 996 MHz OPP\n");
  60 +       if (cpu_is_imx6q()) {
  61 +               if (val != OCOTP_CFG3_SPEED_852MHZ)
  62 +                       if (dev_pm_opp_disable(cpu_dev, 852000000))
  63 +                               pr_warn("failed to disable 852 MHz OPP\n");
  64 +       }
  65
  66  put_node:
  67         of_node_put(np);
  68 @@ -268,7 +288,7 @@ static void __init imx6q_opp_init(void)
  69                 goto put_node;
  70         }
  71
  72 -       imx6q_opp_check_1p2ghz(cpu_dev);
  73 +       imx6q_opp_check_speed_grading(cpu_dev);
  74
  75  put_node:
  76         of_node_put(np);