On Sun, 2017-08-06 at 10:06 +0800, Ryder Lee wrote:

Hi Honghui,

If you plan to send next version, then I would suggest some minor
changes.

On Fri, 2017-08-04 at 20:06 +0800, honghui.zhang at mediatek.com wrote:

quoted

+#define PCIE_CRSTB		BIT(3)
+#define PCIE_PERSTB		BIT(8)
+#define PCI_LINKDOWN_RST_EN	GENMASK(15, 13)

PCIE_LINKDOWN_RST_EN

Thanks, I will change it in the next version.

quoted

+#define PCIE_LINK_STATUS_V2	0x804
+#define PCIE_PORT_LINKUP_V2	BIT(10)
+
+
+static int mtk_pcie_hw_rd_cfg(struct mtk_pcie_port *port, u32 bus, u32 devfn,
+			      int where, int size, u32 *val)
+{
+	int reg, shift = 8 * (where & 3);

int reg => u32

sharp eyes, thanks.

quoted

+	/* Write PCIe Configuration Transaction Header for cfgrd */
+	writel(CFG_HEADER_DW0(CFG_WRRD_TYPE_0, CFG_RD_FMT),
+	       port->base + PCIE_CFG_HEADER0);
+	writel(CFG_HEADER_DW1(where, size), port->base + PCIE_CFG_HEADER1);
+	writel(CFG_HEADER_DW2(where, PCI_FUNC(devfn), PCI_SLOT(devfn), bus),
+	       port->base + PCIE_CFG_HEADER2);
+
+	/* Trigger h/w to transmit Cfgrd TLP */
+	reg = readl(port->base + PCIE_APP_TLP_REQ);
+	writel(reg | APP_CFG_REQ, port->base + PCIE_APP_TLP_REQ);
+
+	/* Check completion status */
+	if (mtk_pcie_check_cfg_cpld(port))
+		return PCIBIOS_SET_FAILED;
+
+	/* Read cpld payload of Cfgrd */
+	*val = readl(port->base + PCIE_CFG_RDATA);
+
+	switch (size) {
+	case 4:
+		break;
+	case 3:
+		*val = (*val >> shift) & 0xffffff;
+		break;
+	case 2:
+		*val = (*val >> shift) & 0xffff;
+		break;
+	case 1:
+		*val = (*val >> shift) & 0xff;
+		break;
+	default:
+		return PCIBIOS_BAD_REGISTER_NUMBER;
+	}

Do we really need case 3? I guess case 1, 2 or 4 should be enough.

I will change this as the following snippet:
	if (size == 1)
		*val = (*val >> (8 * (where & 3))) & 0xff;
	else if (size == 2)
		*val = (*val >> (8 * (where & 3))) & 0xffff;

thanks.

quoted

+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int mtk_pcie_hw_wr_cfg(struct mtk_pcie_port *port, u32 bus, u32 devfn,
+			      int where, int size, u32 val)
+{
+	/* Write PCIe Configuration Transaction Header for Cfgwr */
+	writel(CFG_HEADER_DW0(CFG_WRRD_TYPE_0, CFG_WR_FMT),
+	       port->base + PCIE_CFG_HEADER0);
+	writel(CFG_HEADER_DW1(where, size), port->base + PCIE_CFG_HEADER1);
+	writel(CFG_HEADER_DW2(where, PCI_FUNC(devfn), PCI_SLOT(devfn), bus),
+	       port->base + PCIE_CFG_HEADER2);
+
+	/* Write cfgwr data */
+	val = val << 8 * (where & 3);
+	writel(val, port->base + PCIE_CFG_WDATA);
+
+	/* Trigger h/w to transmit Cfgwr TLP */
+	val = readl(port->base + PCIE_APP_TLP_REQ);
+	val |= APP_CFG_REQ;
+	writel(val, port->base + PCIE_APP_TLP_REQ);
+
+	/* Check completion status */
+	return mtk_pcie_check_cfg_cpld(port);
+}
+
+static int mtk_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
+				int where, int size, u32 *val)
+{
+	struct mtk_pcie_port *port = NULL, *iter, *tmp;
+	struct mtk_pcie *pcie = bus->sysdata;
+	u32 bn = bus->number;
+	int ret;
+
+	list_for_each_entry_safe(iter, tmp, &pcie->ports, list)
+		if (iter->index == PCI_SLOT(devfn)) {
+			port = iter;
+			break;
+		}
+
+	if (!port) {
+		*val = ~0;
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}

list_for_each_entry(), since you don't really remove or free something.

I know you need to find port->base to write/read configuration space. I
think it's better to move this part to another function. You can take a
look at pci-mvebu.c mvebu_pcie_find_portmvebu().

Sure, I will add the mtk_pcie_find_port interface, then the code is a
bit more readable.

thanks.

quoted

+	ret = mtk_pcie_hw_rd_cfg(port, bn, devfn, where, size, val);
+	if (ret)
+		*val = ~0;
+
+	return ret;
+}
+
+static int mtk_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
+				 int where, int size, u32 val)
+{
+	struct mtk_pcie_port *port = NULL, *iter, *tmp;
+	struct mtk_pcie *pcie = bus->sysdata;
+	u32 bn = bus->number;
+
+	list_for_each_entry_safe(iter, tmp, &pcie->ports, list)
+		if (iter->index == PCI_SLOT(devfn)) {
+			port = iter;
+			break;
+		}
+
+	if (!port)
+		return PCIBIOS_DEVICE_NOT_FOUND;

Ditto.

quoted

+	return mtk_pcie_hw_wr_cfg(port, bn, devfn, where, size, val);
+}
+
+static struct pci_ops mtk_pcie_ops_v2 = {
+	.read  = mtk_pcie_config_read,
+	.write = mtk_pcie_config_write,
+};
+
+static int mtk_pcie_startup_ports_v2(struct mtk_pcie_port *port)
+{
+	struct mtk_pcie *pcie = port->pcie;
+	struct resource *mem = &pcie->mem;
+	u32 val;
+	size_t size;
+	int err;
+
+	/* mt7622 platforms need to enable LTSSM and ASPM from PCIe subsys */
+	if (pcie->base) {
+		val = readl(pcie->base + PCIE_SYS_CFG_V2);
+		val |= PCIE_CSR_LTSSM_EN(port->index) |
+		       PCIE_CSR_ASPM_L1_EN(port->index);
+		writel(val, pcie->base + PCIE_SYS_CFG_V2);
+	}
+
+	/* Assert all reset signals */
+	writel(0, port->base + PCIE_RST_CTRL);
+
+	/*
+	 * Enable PCIe link down reset, if link status changed from link up to
+	 * link down, this will reset MAC control registers and configuration
+	 * space.
+	 */
+	writel(PCI_LINKDOWN_RST_EN, port->base + PCIE_RST_CTRL);
+
+	/* De-assert PHY, PE, PIPE, MAC and configuration reset	*/
+	val = readl(port->base + PCIE_RST_CTRL);
+	val |= PCIE_PHY_RSTB | PCIE_PERSTB | PCIE_PIPE_SRSTB |
+	       PCIE_MAC_SRSTB | PCIE_CRSTB;
+	writel(val, port->base + PCIE_RST_CTRL);
+
+	/* PCIe v2.0 need at least 100ms delay to train from Gen1 to Gen2 */

/* 100ms timeout value should be enough for Gen1/2 training */ for
consistency.

quoted

+	err = readl_poll_timeout(port->base + PCIE_LINK_STATUS_V2, val,
+				 !!(val & PCIE_PORT_LINKUP_V2), 20,
+				 100 * USEC_PER_MSEC);
+	if (err)
+		return -ETIMEDOUT;
+
+	/* Set INTx mask */
+	val = readl(port->base + PCIE_INT_MASK);
+	val &= ~INTX_MASK;
+	writel(val, port->base + PCIE_INT_MASK);
+
+	/* Set AHB to PCIe translation windows */
+	size = mem->end - mem->start;
+	val = AHB2PCIE_BASEL(mem->start) | AHB2PCIE_SIZE(fls(size));
+	writel(val, port->base + PCIE_AHB_TRANS_BASE0_L);
+
+	val = AHB2PCIE_BASEH(mem->start);
+	writel(val, port->base + PCIE_AHB_TRANS_BASE0_H);
+
+	/* Set PCIe to AXI translation memory space.*/
+	val = fls(0xffffffff) | WIN_ENABLE;
+	writel(val, port->base + PCIE_AXI_WINDOW0);
+
+	return 0;
+}

Ryder