target/linux/bcm53xx/patches-4.3/047-clk-iproc-Add-PLL-base-write-function.patch

   1 From acbb7a3de7e4d83b23c0bbb3eaf77d15a041d865 Mon Sep 17 00:00:00 2001
   2 From: Jon Mason <jonmason@broadcom.com>
   3 Date: Thu, 15 Oct 2015 15:48:28 -0400
   4 Subject: [PATCH 47/50] clk: iproc: Add PLL base write function
   5
   6 All writes to the PLL base address must be flushed if the
   7 IPROC_CLK_NEEDS_READ_BACK flag is set.  If we add a function to make the
   8 necessary write and reads, we can make sure that any future code which
   9 makes PLL base writes will do the correct thing.
  10
  11 Signed-off-by: Jon Mason <jonmason@broadcom.com>
  12 ---
  13  drivers/clk/bcm/clk-iproc-pll.c | 80 +++++++++++++++++------------------------
  14  1 file changed, 33 insertions(+), 47 deletions(-)
  15
  16 --- a/drivers/clk/bcm/clk-iproc-pll.c
  17 +++ b/drivers/clk/bcm/clk-iproc-pll.c
  18 @@ -137,6 +137,18 @@ static int pll_wait_for_lock(struct ipro
  19         return -EIO;
  20  }
  21
  22 +static void iproc_pll_write(const struct iproc_pll *pll, void __iomem *base,
  23 +                           const u32 offset, u32 val)
  24 +{
  25 +       const struct iproc_pll_ctrl *ctrl = pll->ctrl;
  26 +
  27 +       writel(val, base + offset);
  28 +
  29 +       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK &&
  30 +                    base == pll->pll_base))
  31 +               val = readl(base + offset);
  32 +}
  33 +
  34  static void __pll_disable(struct iproc_pll *pll)
  35  {
  36         const struct iproc_pll_ctrl *ctrl = pll->ctrl;
  37 @@ -145,27 +157,24 @@ static void __pll_disable(struct iproc_p
  38         if (ctrl->flags & IPROC_CLK_PLL_ASIU) {
  39                 val = readl(pll->asiu_base + ctrl->asiu.offset);
  40                 val &= ~(1 << ctrl->asiu.en_shift);
  41 -               writel(val, pll->asiu_base + ctrl->asiu.offset);
  42 +               iproc_pll_write(pll, pll->asiu_base, ctrl->asiu.offset, val);
  43         }
  44
  45         if (ctrl->flags & IPROC_CLK_EMBED_PWRCTRL) {
  46                 val = readl(pll->pll_base + ctrl->aon.offset);
  47                 val |= (bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);
  48 -               writel(val, pll->pll_base + ctrl->aon.offset);
  49 -
  50 -               if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
  51 -                       readl(pll->pll_base + ctrl->aon.offset);
  52 +               iproc_pll_write(pll, pll->pll_base, ctrl->aon.offset, val);
  53         }
  54
  55         if (pll->pwr_base) {
  56                 /* latch input value so core power can be shut down */
  57                 val = readl(pll->pwr_base + ctrl->aon.offset);
  58                 val |= (1 << ctrl->aon.iso_shift);
  59 -               writel(val, pll->pwr_base + ctrl->aon.offset);
  60 +               iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);
  61
  62                 /* power down the core */
  63                 val &= ~(bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);
  64 -               writel(val, pll->pwr_base + ctrl->aon.offset);
  65 +               iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);
  66         }
  67  }
  68
  69 @@ -177,10 +186,7 @@ static int __pll_enable(struct iproc_pll
  70         if (ctrl->flags & IPROC_CLK_EMBED_PWRCTRL) {
  71                 val = readl(pll->pll_base + ctrl->aon.offset);
  72                 val &= ~(bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);
  73 -               writel(val, pll->pll_base + ctrl->aon.offset);
  74 -
  75 -               if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
  76 -                       readl(pll->pll_base + ctrl->aon.offset);
  77 +               iproc_pll_write(pll, pll->pll_base, ctrl->aon.offset, val);
  78         }
  79
  80         if (pll->pwr_base) {
  81 @@ -188,14 +194,14 @@ static int __pll_enable(struct iproc_pll
  82                 val = readl(pll->pwr_base + ctrl->aon.offset);
  83                 val |= bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift;
  84                 val &= ~(1 << ctrl->aon.iso_shift);
  85 -               writel(val, pll->pwr_base + ctrl->aon.offset);
  86 +               iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);
  87         }
  88
  89         /* certain PLLs also need to be ungated from the ASIU top level */
  90         if (ctrl->flags & IPROC_CLK_PLL_ASIU) {
  91                 val = readl(pll->asiu_base + ctrl->asiu.offset);
  92                 val |= (1 << ctrl->asiu.en_shift);
  93 -               writel(val, pll->asiu_base + ctrl->asiu.offset);
  94 +               iproc_pll_write(pll, pll->asiu_base, ctrl->asiu.offset, val);
  95         }
  96
  97         return 0;
  98 @@ -209,9 +215,7 @@ static void __pll_put_in_reset(struct ip
  99
 100         val = readl(pll->pll_base + reset->offset);
 101         val &= ~(1 << reset->reset_shift | 1 << reset->p_reset_shift);
 102 -       writel(val, pll->pll_base + reset->offset);
 103 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 104 -               readl(pll->pll_base + reset->offset);
 105 +       iproc_pll_write(pll, pll->pll_base, reset->offset, val);
 106  }
 107
 108  static void __pll_bring_out_reset(struct iproc_pll *pll, unsigned int kp,
 109 @@ -228,9 +232,7 @@ static void __pll_bring_out_reset(struct
 110         val |=  ki << reset->ki_shift | kp << reset->kp_shift |
 111                 ka << reset->ka_shift;
 112         val |= 1 << reset->reset_shift | 1 << reset->p_reset_shift;
 113 -       writel(val, pll->pll_base + reset->offset);
 114 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 115 -               readl(pll->pll_base + reset->offset);
 116 +       iproc_pll_write(pll, pll->pll_base, reset->offset, val);
 117  }
 118
 119  static int pll_set_rate(struct iproc_clk *clk, unsigned int rate_index,
 120 @@ -285,9 +287,8 @@ static int pll_set_rate(struct iproc_clk
 121         /* put PLL in reset */
 122         __pll_put_in_reset(pll);
 123
 124 -       writel(0, pll->pll_base + ctrl->vco_ctrl.u_offset);
 125 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 126 -               readl(pll->pll_base + ctrl->vco_ctrl.u_offset);
 127 +       iproc_pll_write(pll, pll->pll_base, ctrl->vco_ctrl.u_offset, 0);
 128 +
 129         val = readl(pll->pll_base + ctrl->vco_ctrl.l_offset);
 130
 131         if (rate >= VCO_LOW && rate < VCO_MID)
 132 @@ -298,17 +299,13 @@ static int pll_set_rate(struct iproc_clk
 133         else
 134                 val |= (1 << PLL_VCO_HIGH_SHIFT);
 135
 136 -       writel(val, pll->pll_base + ctrl->vco_ctrl.l_offset);
 137 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 138 -               readl(pll->pll_base + ctrl->vco_ctrl.l_offset);
 139 +       iproc_pll_write(pll, pll->pll_base, ctrl->vco_ctrl.l_offset, val);
 140
 141         /* program integer part of NDIV */
 142         val = readl(pll->pll_base + ctrl->ndiv_int.offset);
 143         val &= ~(bit_mask(ctrl->ndiv_int.width) << ctrl->ndiv_int.shift);
 144         val |= vco->ndiv_int << ctrl->ndiv_int.shift;
 145 -       writel(val, pll->pll_base + ctrl->ndiv_int.offset);
 146 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 147 -               readl(pll->pll_base + ctrl->ndiv_int.offset);
 148 +       iproc_pll_write(pll, pll->pll_base, ctrl->ndiv_int.offset, val);
 149
 150         /* program fractional part of NDIV */
 151         if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
 152 @@ -316,18 +313,15 @@ static int pll_set_rate(struct iproc_clk
 153                 val &= ~(bit_mask(ctrl->ndiv_frac.width) <<
 154                          ctrl->ndiv_frac.shift);
 155                 val |= vco->ndiv_frac << ctrl->ndiv_frac.shift;
 156 -               writel(val, pll->pll_base + ctrl->ndiv_frac.offset);
 157 -               if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 158 -                       readl(pll->pll_base + ctrl->ndiv_frac.offset);
 159 +               iproc_pll_write(pll, pll->pll_base, ctrl->ndiv_frac.offset,
 160 +                               val);
 161         }
 162
 163         /* program PDIV */
 164         val = readl(pll->pll_base + ctrl->pdiv.offset);
 165         val &= ~(bit_mask(ctrl->pdiv.width) << ctrl->pdiv.shift);
 166         val |= vco->pdiv << ctrl->pdiv.shift;
 167 -       writel(val, pll->pll_base + ctrl->pdiv.offset);
 168 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 169 -               readl(pll->pll_base + ctrl->pdiv.offset);
 170 +       iproc_pll_write(pll, pll->pll_base, ctrl->pdiv.offset, val);
 171
 172         __pll_bring_out_reset(pll, kp, ka, ki);
 173
 174 @@ -464,14 +458,12 @@ static int iproc_clk_enable(struct clk_h
 175         /* channel enable is active low */
 176         val = readl(pll->pll_base + ctrl->enable.offset);
 177         val &= ~(1 << ctrl->enable.enable_shift);
 178 -       writel(val, pll->pll_base + ctrl->enable.offset);
 179 +       iproc_pll_write(pll, pll->pll_base, ctrl->enable.offset, val);
 180
 181         /* also make sure channel is not held */
 182         val = readl(pll->pll_base + ctrl->enable.offset);
 183         val &= ~(1 << ctrl->enable.hold_shift);
 184 -       writel(val, pll->pll_base + ctrl->enable.offset);
 185 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 186 -               readl(pll->pll_base + ctrl->enable.offset);
 187 +       iproc_pll_write(pll, pll->pll_base, ctrl->enable.offset, val);
 188
 189         return 0;
 190  }
 191 @@ -488,9 +480,7 @@ static void iproc_clk_disable(struct clk
 192
 193         val = readl(pll->pll_base + ctrl->enable.offset);
 194         val |= 1 << ctrl->enable.enable_shift;
 195 -       writel(val, pll->pll_base + ctrl->enable.offset);
 196 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 197 -               readl(pll->pll_base + ctrl->enable.offset);
 198 +       iproc_pll_write(pll, pll->pll_base, ctrl->enable.offset, val);
 199  }
 200
 201  static unsigned long iproc_clk_recalc_rate(struct clk_hw *hw,
 202 @@ -559,9 +549,7 @@ static int iproc_clk_set_rate(struct clk
 203                 val &= ~(bit_mask(ctrl->mdiv.width) << ctrl->mdiv.shift);
 204                 val |= div << ctrl->mdiv.shift;
 205         }
 206 -       writel(val, pll->pll_base + ctrl->mdiv.offset);
 207 -       if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 208 -               readl(pll->pll_base + ctrl->mdiv.offset);
 209 +       iproc_pll_write(pll, pll->pll_base, ctrl->mdiv.offset, val);
 210         clk->rate = parent_rate / div;
 211
 212         return 0;
 213 @@ -588,9 +576,7 @@ static void iproc_pll_sw_cfg(struct ipro
 214
 215                 val = readl(pll->pll_base + ctrl->sw_ctrl.offset);
 216                 val |= BIT(ctrl->sw_ctrl.shift);
 217 -               writel(val, pll->pll_base + ctrl->sw_ctrl.offset);
 218 -               if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK))
 219 -                       readl(pll->pll_base + ctrl->sw_ctrl.offset);
 220 +               iproc_pll_write(pll, pll->pll_base, ctrl->sw_ctrl.offset, val);
 221         }
 222  }
 223