[PATCH v3 5/6] PCI: mediatek: Add new generation controller support
From: ryder.lee@mediatek.com (Ryder Lee)
Date: 2017-08-06 02:06:40
Also in:
linux-devicetree, linux-mediatek, linux-pci, lkml
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:
+#define PCIE_CRSTB BIT(3) +#define PCIE_PERSTB BIT(8) +#define PCI_LINKDOWN_RST_EN GENMASK(15, 13)
PCIE_LINKDOWN_RST_EN
+#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
+ /* 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.
+ 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().
+ 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.
+ 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.
+ 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