target/linux/ipq806x/patches-4.9/0071-3-PCI-qcom-Fixed-IPQ806x-PCIE-init-changes.patch

   1 From eddd13215d0f2b549ebc5f0e8796d5b1231f90a0 Mon Sep 17 00:00:00 2001
   2 From: Sham Muthayyan <smuthayy@codeaurora.org>
   3 Date: Tue, 19 Jul 2016 19:58:22 +0530
   4 Subject: PCI: qcom: Fixed IPQ806x PCIE init changes
   5
   6 Change-Id: Ic319b1aec27a47809284759f8fcb6a8815b7cf7e
   7 Signed-off-by: Sham Muthayyan <smuthayy@codeaurora.org>
   8 ---
   9  drivers/pci/host/pcie-qcom.c | 62 +++++++++++++++++++++++++++++++++++++-------
  10  1 file changed, 53 insertions(+), 9 deletions(-)
  11
  12 --- a/drivers/pci/host/pcie-qcom.c
  13 +++ b/drivers/pci/host/pcie-qcom.c
  14 @@ -37,7 +37,13 @@
  15  #include "pcie-designware.h"
  16
  17  #define PCIE20_PARF_PHY_CTRL                   0x40
  18 +#define PHY_CTRL_PHY_TX0_TERM_OFFSET_MASK      (0x1f << 16)
  19 +#define PHY_CTRL_PHY_TX0_TERM_OFFSET(x)                (x << 16)
  20 +
  21  #define PCIE20_PARF_PHY_REFCLK                 0x4C
  22 +#define REF_SSP_EN                             BIT(16)
  23 +#define REF_USE_PAD                            BIT(12)
  24 +
  25  #define PCIE20_PARF_DBI_BASE_ADDR              0x168
  26  #define PCIE20_PARF_SLV_ADDR_SPACE_SIZE                0x16c
  27  #define PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT      0x178
  28 @@ -48,6 +54,18 @@
  29  #define PCIE20_CAP                             0x70
  30
  31  #define PERST_DELAY_US                         1000
  32 +/* PARF registers */
  33 +#define PCIE20_PARF_PCS_DEEMPH                 0x34
  34 +#define PCS_DEEMPH_TX_DEEMPH_GEN1(x)           (x << 16)
  35 +#define PCS_DEEMPH_TX_DEEMPH_GEN2_3_5DB(x)     (x << 8)
  36 +#define PCS_DEEMPH_TX_DEEMPH_GEN2_6DB(x)       (x << 0)
  37 +
  38 +#define PCIE20_PARF_PCS_SWING                  0x38
  39 +#define PCS_SWING_TX_SWING_FULL(x)             (x << 8)
  40 +#define PCS_SWING_TX_SWING_LOW(x)              (x << 0)
  41 +
  42 +#define PCIE20_PARF_CONFIG_BITS                        0x50
  43 +#define PHY_RX0_EQ(x)                          (x << 24)
  44
  45  struct qcom_pcie_resources_v0 {
  46         struct clk *iface_clk;
  47 @@ -64,6 +82,7 @@ struct qcom_pcie_resources_v0 {
  48         struct regulator *vdda;
  49         struct regulator *vdda_phy;
  50         struct regulator *vdda_refclk;
  51 +       uint8_t phy_tx0_term_offset;
  52  };
  53
  54  struct qcom_pcie_resources_v1 {
  55 @@ -100,6 +119,16 @@ struct qcom_pcie {
  56
  57  #define to_qcom_pcie(x)                container_of(x, struct qcom_pcie, pp)
  58
  59 +static inline void
  60 +writel_masked(void __iomem *addr, u32 clear_mask, u32 set_mask)
  61 +{
  62 +       u32 val = readl(addr);
  63 +
  64 +       val &= ~clear_mask;
  65 +       val |= set_mask;
  66 +       writel(val, addr);
  67 +}
  68 +
  69  static void qcom_ep_reset_assert(struct qcom_pcie *pcie)
  70  {
  71         gpiod_set_value(pcie->reset, 1);
  72 @@ -195,6 +224,10 @@ static int qcom_pcie_get_resources_v0(st
  73         if (IS_ERR(res->ext_reset))
  74                 return PTR_ERR(res->ext_reset);
  75
  76 +       if (of_property_read_u8(dev->of_node, "phy-tx0-term-offset",
  77 +                               &res->phy_tx0_term_offset))
  78 +               res->phy_tx0_term_offset = 0;
  79 +
  80         return 0;
  81  }
  82
  83 @@ -254,7 +287,6 @@ static int qcom_pcie_init_v0(struct qcom
  84  {
  85         struct qcom_pcie_resources_v0 *res = &pcie->res.v0;
  86         struct device *dev = pcie->pp.dev;
  87 -       u32 val;
  88         int ret;
  89
  90         ret = reset_control_assert(res->ahb_reset);
  91 @@ -323,15 +355,27 @@ static int qcom_pcie_init_v0(struct qcom
  92                 goto err_deassert_ahb;
  93         }
  94
  95 -       /* enable PCIe clocks and resets */
  96 -       val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
  97 -       val &= ~BIT(0);
  98 -       writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
  99 -
 100 -       /* enable external reference clock */
 101 -       val = readl(pcie->parf + PCIE20_PARF_PHY_REFCLK);
 102 -       val |= BIT(16);
 103 -       writel(val, pcie->parf + PCIE20_PARF_PHY_REFCLK);
 104 +       writel_masked(pcie->parf + PCIE20_PARF_PHY_CTRL, BIT(0), 0);
 105 +
 106 +       /* Set Tx termination offset */
 107 +       writel_masked(pcie->parf + PCIE20_PARF_PHY_CTRL,
 108 +                     PHY_CTRL_PHY_TX0_TERM_OFFSET_MASK,
 109 +                     PHY_CTRL_PHY_TX0_TERM_OFFSET(res->phy_tx0_term_offset));
 110 +
 111 +       /* PARF programming */
 112 +       writel(PCS_DEEMPH_TX_DEEMPH_GEN1(0x18) |
 113 +              PCS_DEEMPH_TX_DEEMPH_GEN2_3_5DB(0x18) |
 114 +              PCS_DEEMPH_TX_DEEMPH_GEN2_6DB(0x22),
 115 +              pcie->parf + PCIE20_PARF_PCS_DEEMPH);
 116 +       writel(PCS_SWING_TX_SWING_FULL(0x78) |
 117 +              PCS_SWING_TX_SWING_LOW(0x78),
 118 +              pcie->parf + PCIE20_PARF_PCS_SWING);
 119 +       writel(PHY_RX0_EQ(0x4), pcie->parf + PCIE20_PARF_CONFIG_BITS);
 120 +
 121 +       /* Enable reference clock */
 122 +       writel_masked(pcie->parf + PCIE20_PARF_PHY_REFCLK,
 123 +                     REF_USE_PAD, REF_SSP_EN);
 124 +
 125
 126         ret = reset_control_deassert(res->phy_reset);
 127         if (ret) {