target/linux/ar71xx/patches-3.3/137-MIPS-ath79-fix-CPU-DDR-frequency-calculation-for-SRI.patch

   1 From 3f735e202d5099a5b7c621443bea365b87b0e3bb Mon Sep 17 00:00:00 2001
   2 From: Gabor Juhos <juhosg@openwrt.org>
   3 Date: Sat, 8 Sep 2012 12:12:50 +0200
   4 Subject: [PATCH] MIPS: ath79: fix CPU/DDR frequency calculation for SRIF PLLs
   5
   6 Besides the CPU and DDR PLLs, the CPU and DDR frequencies
   7 can be derived from other PLLs in the SRIF block on the
   8 AR934x SoCs. The current code does not checks if the SRIF
   9 PLLs are used and this can lead to incorrectly calculated
  10 CPU/DDR frequencies.
  11
  12 Fix it by calculating the frequencies from SRIF PLLs if
  13 those are used on a given board.
  14
  15 Cc: <stable@vger.kernel.org>
  16 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
  17 ---
  18 This depends on the following patch:
  19 'MIPS: ath79: use correct fractional dividers for {CPU,DDR}_PLL on AR934x'
  20 https://patchwork.linux-mips.org/patch/4305/
  21
  22  arch/mips/ath79/clock.c                        |  109 ++++++++++++++++++------
  23  arch/mips/include/asm/mach-ath79/ar71xx_regs.h |   23 +++++
  24  2 files changed, 104 insertions(+), 28 deletions(-)
  25
  26 --- a/arch/mips/ath79/clock.c
  27 +++ b/arch/mips/ath79/clock.c
  28 @@ -17,6 +17,8 @@
  29  #include <linux/err.h>
  30  #include <linux/clk.h>
  31
  32 +#include <asm/div64.h>
  33 +
  34  #include <asm/mach-ath79/ath79.h>
  35  #include <asm/mach-ath79/ar71xx_regs.h>
  36  #include "common.h"
  37 @@ -166,11 +168,34 @@ static void __init ar933x_clocks_init(vo
  38         ath79_uart_clk.rate = ath79_ref_clk.rate;
  39  }
  40
  41 +static u32 __init ar934x_get_pll_freq(u32 ref, u32 ref_div, u32 nint, u32 nfrac,
  42 +                                     u32 frac, u32 out_div)
  43 +{
  44 +       u64 t;
  45 +       u32 ret;
  46 +
  47 +       t = ath79_ref_clk.rate;
  48 +       t *= nint;
  49 +       do_div(t, ref_div);
  50 +       ret = t;
  51 +
  52 +       t = ath79_ref_clk.rate;
  53 +       t *= nfrac;
  54 +       do_div(t, ref_div * frac);
  55 +       ret += t;
  56 +
  57 +       ret /= (1 << out_div);
  58 +       return ret;
  59 +}
  60 +
  61  static void __init ar934x_clocks_init(void)
  62  {
  63 -       u32 pll, out_div, ref_div, nint, frac, clk_ctrl, postdiv;
  64 +       u32 pll, out_div, ref_div, nint, nfrac, frac, clk_ctrl, postdiv;
  65         u32 cpu_pll, ddr_pll;
  66         u32 bootstrap;
  67 +       void __iomem *dpll_base;
  68 +
  69 +       dpll_base = ioremap(AR934X_SRIF_BASE, AR934X_SRIF_SIZE);
  70
  71         bootstrap = ath79_reset_rr(AR934X_RESET_REG_BOOTSTRAP);
  72         if (bootstrap & AR934X_BOOTSTRAP_REF_CLK_40)
  73 @@ -178,33 +203,59 @@ static void __init ar934x_clocks_init(vo
  74         else
  75                 ath79_ref_clk.rate = 25 * 1000 * 1000;
  76
  77 -       pll = ath79_pll_rr(AR934X_PLL_CPU_CONFIG_REG);
  78 -       out_div = (pll >> AR934X_PLL_CPU_CONFIG_OUTDIV_SHIFT) &
  79 -                 AR934X_PLL_CPU_CONFIG_OUTDIV_MASK;
  80 -       ref_div = (pll >> AR934X_PLL_CPU_CONFIG_REFDIV_SHIFT) &
  81 -                 AR934X_PLL_CPU_CONFIG_REFDIV_MASK;
  82 -       nint = (pll >> AR934X_PLL_CPU_CONFIG_NINT_SHIFT) &
  83 -              AR934X_PLL_CPU_CONFIG_NINT_MASK;
  84 -       frac = (pll >> AR934X_PLL_CPU_CONFIG_NFRAC_SHIFT) &
  85 -              AR934X_PLL_CPU_CONFIG_NFRAC_MASK;
  86 -
  87 -       cpu_pll = nint * ath79_ref_clk.rate / ref_div;
  88 -       cpu_pll += frac * ath79_ref_clk.rate / (ref_div * (1 << 6));
  89 -       cpu_pll /= (1 << out_div);
  90 -
  91 -       pll = ath79_pll_rr(AR934X_PLL_DDR_CONFIG_REG);
  92 -       out_div = (pll >> AR934X_PLL_DDR_CONFIG_OUTDIV_SHIFT) &
  93 -                 AR934X_PLL_DDR_CONFIG_OUTDIV_MASK;
  94 -       ref_div = (pll >> AR934X_PLL_DDR_CONFIG_REFDIV_SHIFT) &
  95 -                 AR934X_PLL_DDR_CONFIG_REFDIV_MASK;
  96 -       nint = (pll >> AR934X_PLL_DDR_CONFIG_NINT_SHIFT) &
  97 -              AR934X_PLL_DDR_CONFIG_NINT_MASK;
  98 -       frac = (pll >> AR934X_PLL_DDR_CONFIG_NFRAC_SHIFT) &
  99 -              AR934X_PLL_DDR_CONFIG_NFRAC_MASK;
 100 -
 101 -       ddr_pll = nint * ath79_ref_clk.rate / ref_div;
 102 -       ddr_pll += frac * ath79_ref_clk.rate / (ref_div * (1 << 10));
 103 -       ddr_pll /= (1 << out_div);
 104 +       pll = __raw_readl(dpll_base + AR934X_SRIF_CPU_DPLL2_REG);
 105 +       if (pll & AR934X_SRIF_DPLL2_LOCAL_PLL) {
 106 +               out_div = (pll >> AR934X_SRIF_DPLL2_OUTDIV_SHIFT) &
 107 +                         AR934X_SRIF_DPLL2_OUTDIV_MASK;
 108 +               pll = __raw_readl(dpll_base + AR934X_SRIF_CPU_DPLL1_REG);
 109 +               nint = (pll >> AR934X_SRIF_DPLL1_NINT_SHIFT) &
 110 +                      AR934X_SRIF_DPLL1_NINT_MASK;
 111 +               nfrac = pll & AR934X_SRIF_DPLL1_NFRAC_MASK;
 112 +               ref_div = (pll >> AR934X_SRIF_DPLL1_REFDIV_SHIFT) &
 113 +                         AR934X_SRIF_DPLL1_REFDIV_MASK;
 114 +               frac = 1 << 18;
 115 +       } else {
 116 +               pll = ath79_pll_rr(AR934X_PLL_CPU_CONFIG_REG);
 117 +               out_div = (pll >> AR934X_PLL_CPU_CONFIG_OUTDIV_SHIFT) &
 118 +                       AR934X_PLL_CPU_CONFIG_OUTDIV_MASK;
 119 +               ref_div = (pll >> AR934X_PLL_CPU_CONFIG_REFDIV_SHIFT) &
 120 +                         AR934X_PLL_CPU_CONFIG_REFDIV_MASK;
 121 +               nint = (pll >> AR934X_PLL_CPU_CONFIG_NINT_SHIFT) &
 122 +                      AR934X_PLL_CPU_CONFIG_NINT_MASK;
 123 +               nfrac = (pll >> AR934X_PLL_CPU_CONFIG_NFRAC_SHIFT) &
 124 +                       AR934X_PLL_CPU_CONFIG_NFRAC_MASK;
 125 +               frac = 1 << 6;
 126 +       }
 127 +
 128 +       cpu_pll = ar934x_get_pll_freq(ath79_ref_clk.rate, ref_div, nint,
 129 +                                     nfrac, frac, out_div);
 130 +
 131 +       pll = __raw_readl(dpll_base + AR934X_SRIF_DDR_DPLL2_REG);
 132 +       if (pll & AR934X_SRIF_DPLL2_LOCAL_PLL) {
 133 +               out_div = (pll >> AR934X_SRIF_DPLL2_OUTDIV_SHIFT) &
 134 +                         AR934X_SRIF_DPLL2_OUTDIV_MASK;
 135 +               pll = __raw_readl(dpll_base + AR934X_SRIF_DDR_DPLL1_REG);
 136 +               nint = (pll >> AR934X_SRIF_DPLL1_NINT_SHIFT) &
 137 +                      AR934X_SRIF_DPLL1_NINT_MASK;
 138 +               nfrac = pll & AR934X_SRIF_DPLL1_NFRAC_MASK;
 139 +               ref_div = (pll >> AR934X_SRIF_DPLL1_REFDIV_SHIFT) &
 140 +                         AR934X_SRIF_DPLL1_REFDIV_MASK;
 141 +               frac = 1 << 18;
 142 +       } else {
 143 +               pll = ath79_pll_rr(AR934X_PLL_DDR_CONFIG_REG);
 144 +               out_div = (pll >> AR934X_PLL_DDR_CONFIG_OUTDIV_SHIFT) &
 145 +                         AR934X_PLL_DDR_CONFIG_OUTDIV_MASK;
 146 +               ref_div = (pll >> AR934X_PLL_DDR_CONFIG_REFDIV_SHIFT) &
 147 +                          AR934X_PLL_DDR_CONFIG_REFDIV_MASK;
 148 +               nint = (pll >> AR934X_PLL_DDR_CONFIG_NINT_SHIFT) &
 149 +                      AR934X_PLL_DDR_CONFIG_NINT_MASK;
 150 +               nfrac = (pll >> AR934X_PLL_DDR_CONFIG_NFRAC_SHIFT) &
 151 +                       AR934X_PLL_DDR_CONFIG_NFRAC_MASK;
 152 +               frac = 1 << 10;
 153 +       }
 154 +
 155 +       ddr_pll = ar934x_get_pll_freq(ath79_ref_clk.rate, ref_div, nint,
 156 +                                     nfrac, frac, out_div);
 157
 158         clk_ctrl = ath79_pll_rr(AR934X_PLL_CPU_DDR_CLK_CTRL_REG);
 159
 160 @@ -240,6 +291,8 @@ static void __init ar934x_clocks_init(vo
 161
 162         ath79_wdt_clk.rate = ath79_ref_clk.rate;
 163         ath79_uart_clk.rate = ath79_ref_clk.rate;
 164 +
 165 +       iounmap(dpll_base);
 166  }
 167
 168  void __init ath79_clocks_init(void)
 169 --- a/arch/mips/include/asm/mach-ath79/ar71xx_regs.h
 170 +++ b/arch/mips/include/asm/mach-ath79/ar71xx_regs.h
 171 @@ -65,6 +65,8 @@
 172  #define AR934X_WMAC_SIZE       0x20000
 173  #define AR934X_EHCI_BASE       0x1b000000
 174  #define AR934X_EHCI_SIZE       0x200
 175 +#define AR934X_SRIF_BASE       (AR71XX_APB_BASE + 0x00116000)
 176 +#define AR934X_SRIF_SIZE       0x1000
 177
 178  /*
 179   * DDR_CTRL block
 180 @@ -405,4 +407,25 @@
 181  #define AR933X_GPIO_COUNT              30
 182  #define AR934X_GPIO_COUNT              23
 183
 184 +/*
 185 + * SRIF block
 186 + */
 187 +#define AR934X_SRIF_CPU_DPLL1_REG      0x1c0
 188 +#define AR934X_SRIF_CPU_DPLL2_REG      0x1c4
 189 +#define AR934X_SRIF_CPU_DPLL3_REG      0x1c8
 190 +
 191 +#define AR934X_SRIF_DDR_DPLL1_REG      0x240
 192 +#define AR934X_SRIF_DDR_DPLL2_REG      0x244
 193 +#define AR934X_SRIF_DDR_DPLL3_REG      0x248
 194 +
 195 +#define AR934X_SRIF_DPLL1_REFDIV_SHIFT 27
 196 +#define AR934X_SRIF_DPLL1_REFDIV_MASK  0x1f
 197 +#define AR934X_SRIF_DPLL1_NINT_SHIFT   18
 198 +#define AR934X_SRIF_DPLL1_NINT_MASK    0x1ff
 199 +#define AR934X_SRIF_DPLL1_NFRAC_MASK   0x0003ffff
 200 +
 201 +#define AR934X_SRIF_DPLL2_LOCAL_PLL    BIT(30)
 202 +#define AR934X_SRIF_DPLL2_OUTDIV_SHIFT 13
 203 +#define AR934X_SRIF_DPLL2_OUTDIV_MASK  0x7
 204 +
 205  #endif /* __ASM_MACH_AR71XX_REGS_H */