pci/layerscape: fix link and class issues to support ls2085a

1. LS2085a provides PCIE_LUT_DBG register rather than PCIE_LDBG
   to show the link status, so the patch fixes it.
2. Increase the delay time to make sure that link training
   has finished.
3. Return invalid value when accessing multi-function device
4. For LS2085a DBI_RO_WR_EN bit is cleared as default, so we
   must set this bit before change DBI register value.

Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>

diff --git a/drivers/pci/pcie_layerscape.c b/drivers/pci/pcie_layerscape.c
index 1b0b814282461dc4492b02c99927c6bd1dae1519..402c5193e0fc2d4f5267a0c996adc2d8439ebdb6 100644 (file)
--- a/drivers/pci/pcie_layerscape.c
+++ b/drivers/pci/pcie_layerscape.c
@@ -49,11 +49,20 @@
 #define PCIE_ATU_FUNC(x)               (((x) & 0x7) << 16)
 #define PCIE_ATU_UPPER_TARGET          0x91C
 
+/* LUT registers */
+#define PCIE_LUT_BASE          0x80000
+#define PCIE_LUT_DBG           0x7FC
+
+#define PCIE_DBI_RO_WR_EN      0x8bc
+
 #define PCIE_LINK_CAP          0x7c
 #define PCIE_LINK_SPEED_MASK   0xf
 #define PCIE_LINK_STA          0x82
 
-#define PCIE_DBI_SIZE          (4 * 1024) /* 4K */
+#define LTSSM_STATE_MASK       0x3f
+#define LTSSM_PCIE_L0          0x11 /* L0 state */
+
+#define PCIE_DBI_SIZE          0x100000 /* 1M */
 
 struct ls_pcie {
        int idx;
@@ -103,8 +112,6 @@ struct ls_pcie_info {
 
 /* PEX1/2 Misc Ports Status Register */
 #define LTSSM_STATE_SHIFT      20
-#define LTSSM_STATE_MASK       0x3f
-#define LTSSM_PCIE_L0          0x11 /* L0 state */
 
 static int ls_pcie_link_state(struct ls_pcie *pcie)
 {
@@ -121,18 +128,18 @@ static int ls_pcie_link_state(struct ls_pcie *pcie)
        return 1;
 }
 #else
-#define PCIE_LDBG 0x7FC
-
 static int ls_pcie_link_state(struct ls_pcie *pcie)
 {
        u32 state;
 
-       state = readl(pcie->dbi + PCIE_LDBG);
-       if (state)
-               return 1;
+       state = readl(pcie->dbi + PCIE_LUT_BASE + PCIE_LUT_DBG) &
+               LTSSM_STATE_MASK;
+       if (state < LTSSM_PCIE_L0) {
+               debug("....PCIe link error. LTSSM=0x%02x.\n", state);
+               return 0;
+       }
 
-       debug("....PCIe link error.\n");
-       return 0;
+       return 1;
 }
 #endif
 
@@ -148,7 +155,11 @@ static int ls_pcie_link_up(struct ls_pcie *pcie)
        /* Try to download speed to gen1 */
        cap = readl(pcie->dbi + PCIE_LINK_CAP);
        writel((cap & (~PCIE_LINK_SPEED_MASK)) | 1, pcie->dbi + PCIE_LINK_CAP);
-       udelay(2000);
+       /*
+        * Notice: the following delay has critical impact on link training
+        * if too short (<30ms) the link doesn't get up.
+        */
+       mdelay(100);
        state = ls_pcie_link_state(pcie);
        if (state)
                return state;
@@ -250,6 +261,10 @@ static int ls_pcie_addr_valid(struct pci_controller *hose, pci_dev_t d)
        if (PCI_DEV(d) > 0)
                return -EINVAL;
 
+       /* Controller does not support multi-function in RC mode */
+       if ((PCI_BUS(d) == hose->first_busno) && (PCI_FUNC(d) > 0))
+               return -EINVAL;
+
        return 0;
 }
 
@@ -326,8 +341,12 @@ static void ls_pcie_setup_ctrl(struct ls_pcie *pcie,
        pci_hose_write_config_dword(hose, dev, PCI_BASE_ADDRESS_0, 0);
 
        /* program correct class for RC */
+       writel(1, pcie->dbi + PCIE_DBI_RO_WR_EN);
        pci_hose_write_config_word(hose, dev, PCI_CLASS_DEVICE,
                                   PCI_CLASS_BRIDGE_PCI);
+#ifndef CONFIG_LS102XA
+       writel(0, pcie->dbi + PCIE_DBI_RO_WR_EN);
+#endif
 }
 
 int ls_pcie_init_ctrl(int busno, enum srds_prtcl dev, struct ls_pcie_info *info)
@@ -416,9 +435,9 @@ int ls_pcie_init_ctrl(int busno, enum srds_prtcl dev, struct ls_pcie_info *info)
        }
 
        /* Print the negotiated PCIe link width */
-       pci_hose_read_config_word(hose, dev, PCIE_LINK_STA, &temp16);
-               printf("x%d gen%d, regs @ 0x%lx\n", (temp16 & 0x3f0) >> 4,
-                      (temp16 & 0xf), info->regs);
+       pci_hose_read_config_word(hose, pdev, PCIE_LINK_STA, &temp16);
+       printf("x%d gen%d, regs @ 0x%lx\n", (temp16 & 0x3f0) >> 4,
+              (temp16 & 0xf), info->regs);
 
        if (ep_mode)
                return busno;