[PATCH 01/13] pci: xilinx: Handle size of ecam region properly

[Jiaxun Yang]

Probe size of ecam from devicetree properly and cap accessible
bus number accorading to ecam region size to ensure we don't go
beyond hardware address space.

Also disable all interrupts to ensure errors are handled silently.

Signed-off-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
---
 drivers/pci/pcie_xilinx.c | 53 +++++++++++++++++++++++++++++++++++------------
 1 file changed, 40 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/pcie_xilinx.c b/drivers/pci/pcie_xilinx.c
index a674ab04beee..63058e8e7c5d 100644
--- a/drivers/pci/pcie_xilinx.c
+++ b/drivers/pci/pcie_xilinx.c
@@ -18,14 +18,19 @@
  */
 struct xilinx_pcie {
 	void *cfg_base;
+	pci_size_t size;
+	int first_busno;
 };
 
 /* Register definitions */
-#define XILINX_PCIE_REG_PSCR		0x144
-#define XILINX_PCIE_REG_PSCR_LNKUP	BIT(11)
-#define XILINX_PCIE_REG_RPSC		0x148
-#define XILINX_PCIE_REG_RPSC_BEN	BIT(0)
-
+#define XILINX_PCIE_REG_BRIDGE_INFO			0x130
+#define  XILINX_PCIE_REG_BRIDGE_INFO_ECAMSZ_SHIFT	16
+#define  XILINX_PCIE_REG_BRIDGE_INFO_ECAMSZ_MASK	(0x7 << 16)
+#define XILINX_PCIE_REG_INT_MASK			0x13c
+#define XILINX_PCIE_REG_PSCR				0x144
+#define  XILINX_PCIE_REG_PSCR_LNKUP			BIT(11)
+#define XILINX_PCIE_REG_RPSC				0x148
+#define  XILINX_PCIE_REG_RPSC_BEN			BIT(0)
 /**
  * pcie_xilinx_link_up() - Check whether the PCIe link is up
  * @pcie: Pointer to the PCI controller state
@@ -61,14 +66,18 @@ static int pcie_xilinx_config_address(const struct udevice *udev, pci_dev_t bdf,
 				      uint offset, void **paddress)
 {
 	struct xilinx_pcie *pcie = dev_get_priv(udev);
-	unsigned int bus = PCI_BUS(bdf);
+	unsigned int bus = PCI_BUS(bdf) - pcie->first_busno;
 	unsigned int dev = PCI_DEV(bdf);
 	unsigned int func = PCI_FUNC(bdf);
+	int num_buses = DIV_ROUND_UP(pcie->size, 1 << 16);
 	void *addr;
 
 	if ((bus > 0) && !pcie_xilinx_link_up(pcie))
 		return -ENODEV;
 
+	if (bus > num_buses)
+		return -ENODEV;
+
 	/*
 	 * Busses 0 (host-PCIe bridge) & 1 (its immediate child) are
 	 * limited to a single device each.
@@ -142,20 +151,37 @@ static int pcie_xilinx_of_to_plat(struct udevice *dev)
 	struct xilinx_pcie *pcie = dev_get_priv(dev);
 	fdt_addr_t addr;
 	fdt_size_t size;
-	u32 rpsc;
 
 	addr = dev_read_addr_size(dev, &size);
 	if (addr == FDT_ADDR_T_NONE)
 		return -EINVAL;
 
-	pcie->cfg_base = devm_ioremap(dev, addr, size);
-	if (IS_ERR(pcie->cfg_base))
-		return PTR_ERR(pcie->cfg_base);
+	pcie->cfg_base = map_physmem(addr, size, MAP_NOCACHE);
+	if (!pcie->cfg_base)
+		return -ENOMEM;
+	pcie->size = size;
+	return 0;
+}
 
-	/* Enable the Bridge enable bit */
-	rpsc = __raw_readl(pcie->cfg_base + XILINX_PCIE_REG_RPSC);
+static int pci_xilinx_probe(struct udevice *dev)
+{
+	struct xilinx_pcie *pcie = dev_get_priv(dev);
+	u32 rpsc;
+	int num_buses = DIV_ROUND_UP(pcie->size, 1 << 16);
+
+	pcie->first_busno = dev_seq(dev);
+
+	/* Disable all interrupts */
+	writel(0, pcie->cfg_base + XILINX_PCIE_REG_INT_MASK);
+
+	/* Enable the bridge */
+	rpsc = readl(pcie->cfg_base + XILINX_PCIE_REG_RPSC);
 	rpsc |= XILINX_PCIE_REG_RPSC_BEN;
-	__raw_writel(rpsc, pcie->cfg_base + XILINX_PCIE_REG_RPSC);
+	writel(rpsc, pcie->cfg_base + XILINX_PCIE_REG_RPSC);
+
+	/* Enable access to all possible subordinate buses */
+	writel((0 << 0) | (1 << 8) | (num_buses << 16),
+	       pcie->cfg_base + PCI_PRIMARY_BUS);
 
 	return 0;
 }
@@ -176,5 +202,6 @@ U_BOOT_DRIVER(pcie_xilinx) = {
 	.of_match		= pcie_xilinx_ids,
 	.ops			= &pcie_xilinx_ops,
 	.of_to_plat	= pcie_xilinx_of_to_plat,
+	.probe			= pci_xilinx_probe,
 	.priv_auto	= sizeof(struct xilinx_pcie),
 };

-- 
2.34.1