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-rw-r--r--arch/arm/mach-cns3xxx/pcie.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/arch/arm/mach-cns3xxx/pcie.c b/arch/arm/mach-cns3xxx/pcie.c
new file mode 100644
index 000000000..e92fbd679
--- /dev/null
+++ b/arch/arm/mach-cns3xxx/pcie.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCI-E support for CNS3xxx
+ *
+ * Copyright 2008 Cavium Networks
+ * Richard Liu <richard.liu@caviumnetworks.com>
+ * Copyright 2010 MontaVista Software, LLC.
+ * Anton Vorontsov <avorontsov@mvista.com>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/bug.h>
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <asm/mach/map.h>
+#include "cns3xxx.h"
+#include "core.h"
+
+struct cns3xxx_pcie {
+ void __iomem *host_regs; /* PCI config registers for host bridge */
+ void __iomem *cfg0_regs; /* PCI Type 0 config registers */
+ void __iomem *cfg1_regs; /* PCI Type 1 config registers */
+ unsigned int irqs[2];
+ struct resource res_io;
+ struct resource res_mem;
+ int port;
+ bool linked;
+};
+
+static struct cns3xxx_pcie *sysdata_to_cnspci(void *sysdata)
+{
+ struct pci_sys_data *root = sysdata;
+
+ return root->private_data;
+}
+
+static struct cns3xxx_pcie *pdev_to_cnspci(const struct pci_dev *dev)
+{
+ return sysdata_to_cnspci(dev->sysdata);
+}
+
+static struct cns3xxx_pcie *pbus_to_cnspci(struct pci_bus *bus)
+{
+ return sysdata_to_cnspci(bus->sysdata);
+}
+
+static void __iomem *cns3xxx_pci_map_bus(struct pci_bus *bus,
+ unsigned int devfn, int where)
+{
+ struct cns3xxx_pcie *cnspci = pbus_to_cnspci(bus);
+ int busno = bus->number;
+ int slot = PCI_SLOT(devfn);
+ void __iomem *base;
+
+ /* If there is no link, just show the CNS PCI bridge. */
+ if (!cnspci->linked && busno > 0)
+ return NULL;
+
+ /*
+ * The CNS PCI bridge doesn't fit into the PCI hierarchy, though
+ * we still want to access it.
+ * We place the host bridge on bus 0, and the directly connected
+ * device on bus 1, slot 0.
+ */
+ if (busno == 0) { /* internal PCIe bus, host bridge device */
+ if (devfn == 0) /* device# and function# are ignored by hw */
+ base = cnspci->host_regs;
+ else
+ return NULL; /* no such device */
+
+ } else if (busno == 1) { /* directly connected PCIe device */
+ if (slot == 0) /* device# is ignored by hw */
+ base = cnspci->cfg0_regs;
+ else
+ return NULL; /* no such device */
+ } else /* remote PCI bus */
+ base = cnspci->cfg1_regs + ((busno & 0xf) << 20);
+
+ return base + where + (devfn << 12);
+}
+
+static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val)
+{
+ int ret;
+ u32 mask = (0x1ull << (size * 8)) - 1;
+ int shift = (where % 4) * 8;
+
+ ret = pci_generic_config_read(bus, devfn, where, size, val);
+
+ if (ret == PCIBIOS_SUCCESSFUL && !bus->number && !devfn &&
+ (where & 0xffc) == PCI_CLASS_REVISION)
+ /*
+ * RC's class is 0xb, but Linux PCI driver needs 0x604
+ * for a PCIe bridge. So we must fixup the class code
+ * to 0x604 here.
+ */
+ *val = ((((*val << shift) & 0xff) | (0x604 << 16)) >> shift) & mask;
+
+ return ret;
+}
+
+static int cns3xxx_pci_setup(int nr, struct pci_sys_data *sys)
+{
+ struct cns3xxx_pcie *cnspci = sysdata_to_cnspci(sys);
+ struct resource *res_io = &cnspci->res_io;
+ struct resource *res_mem = &cnspci->res_mem;
+
+ BUG_ON(request_resource(&iomem_resource, res_io) ||
+ request_resource(&iomem_resource, res_mem));
+
+ pci_add_resource_offset(&sys->resources, res_io, sys->io_offset);
+ pci_add_resource_offset(&sys->resources, res_mem, sys->mem_offset);
+
+ return 1;
+}
+
+static struct pci_ops cns3xxx_pcie_ops = {
+ .map_bus = cns3xxx_pci_map_bus,
+ .read = cns3xxx_pci_read_config,
+ .write = pci_generic_config_write,
+};
+
+static int cns3xxx_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+ struct cns3xxx_pcie *cnspci = pdev_to_cnspci(dev);
+ int irq = cnspci->irqs[!!dev->bus->number];
+
+ pr_info("PCIe map irq: %04d:%02x:%02x.%02x slot %d, pin %d, irq: %d\n",
+ pci_domain_nr(dev->bus), dev->bus->number, PCI_SLOT(dev->devfn),
+ PCI_FUNC(dev->devfn), slot, pin, irq);
+
+ return irq;
+}
+
+static struct cns3xxx_pcie cns3xxx_pcie[] = {
+ [0] = {
+ .host_regs = (void __iomem *)CNS3XXX_PCIE0_HOST_BASE_VIRT,
+ .cfg0_regs = (void __iomem *)CNS3XXX_PCIE0_CFG0_BASE_VIRT,
+ .cfg1_regs = (void __iomem *)CNS3XXX_PCIE0_CFG1_BASE_VIRT,
+ .res_io = {
+ .name = "PCIe0 I/O space",
+ .start = CNS3XXX_PCIE0_IO_BASE,
+ .end = CNS3XXX_PCIE0_CFG0_BASE - 1, /* 16 MiB */
+ .flags = IORESOURCE_IO,
+ },
+ .res_mem = {
+ .name = "PCIe0 non-prefetchable",
+ .start = CNS3XXX_PCIE0_MEM_BASE,
+ .end = CNS3XXX_PCIE0_HOST_BASE - 1, /* 176 MiB */
+ .flags = IORESOURCE_MEM,
+ },
+ .irqs = { IRQ_CNS3XXX_PCIE0_RC, IRQ_CNS3XXX_PCIE0_DEVICE, },
+ .port = 0,
+ },
+ [1] = {
+ .host_regs = (void __iomem *)CNS3XXX_PCIE1_HOST_BASE_VIRT,
+ .cfg0_regs = (void __iomem *)CNS3XXX_PCIE1_CFG0_BASE_VIRT,
+ .cfg1_regs = (void __iomem *)CNS3XXX_PCIE1_CFG1_BASE_VIRT,
+ .res_io = {
+ .name = "PCIe1 I/O space",
+ .start = CNS3XXX_PCIE1_IO_BASE,
+ .end = CNS3XXX_PCIE1_CFG0_BASE - 1, /* 16 MiB */
+ .flags = IORESOURCE_IO,
+ },
+ .res_mem = {
+ .name = "PCIe1 non-prefetchable",
+ .start = CNS3XXX_PCIE1_MEM_BASE,
+ .end = CNS3XXX_PCIE1_HOST_BASE - 1, /* 176 MiB */
+ .flags = IORESOURCE_MEM,
+ },
+ .irqs = { IRQ_CNS3XXX_PCIE1_RC, IRQ_CNS3XXX_PCIE1_DEVICE, },
+ .port = 1,
+ },
+};
+
+static void __init cns3xxx_pcie_check_link(struct cns3xxx_pcie *cnspci)
+{
+ int port = cnspci->port;
+ u32 reg;
+ unsigned long time;
+
+ reg = __raw_readl(MISC_PCIE_CTRL(port));
+ /*
+ * Enable Application Request to 1, it will exit L1 automatically,
+ * but when chip back, it will use another clock, still can use 0x1.
+ */
+ reg |= 0x3;
+ __raw_writel(reg, MISC_PCIE_CTRL(port));
+
+ pr_info("PCIe: Port[%d] Enable PCIe LTSSM\n", port);
+ pr_info("PCIe: Port[%d] Check data link layer...", port);
+
+ time = jiffies;
+ while (1) {
+ reg = __raw_readl(MISC_PCIE_PM_DEBUG(port));
+ if (reg & 0x1) {
+ pr_info("Link up.\n");
+ cnspci->linked = 1;
+ break;
+ } else if (time_after(jiffies, time + 50)) {
+ pr_info("Device not found.\n");
+ break;
+ }
+ }
+}
+
+static void cns3xxx_write_config(struct cns3xxx_pcie *cnspci,
+ int where, int size, u32 val)
+{
+ void __iomem *base = cnspci->host_regs + (where & 0xffc);
+ u32 v;
+ u32 mask = (0x1ull << (size * 8)) - 1;
+ int shift = (where % 4) * 8;
+
+ v = readl_relaxed(base);
+
+ v &= ~(mask << shift);
+ v |= (val & mask) << shift;
+
+ writel_relaxed(v, base);
+ readl_relaxed(base);
+}
+
+static void __init cns3xxx_pcie_hw_init(struct cns3xxx_pcie *cnspci)
+{
+ u16 mem_base = cnspci->res_mem.start >> 16;
+ u16 mem_limit = cnspci->res_mem.end >> 16;
+ u16 io_base = cnspci->res_io.start >> 16;
+ u16 io_limit = cnspci->res_io.end >> 16;
+
+ cns3xxx_write_config(cnspci, PCI_PRIMARY_BUS, 1, 0);
+ cns3xxx_write_config(cnspci, PCI_SECONDARY_BUS, 1, 1);
+ cns3xxx_write_config(cnspci, PCI_SUBORDINATE_BUS, 1, 1);
+ cns3xxx_write_config(cnspci, PCI_MEMORY_BASE, 2, mem_base);
+ cns3xxx_write_config(cnspci, PCI_MEMORY_LIMIT, 2, mem_limit);
+ cns3xxx_write_config(cnspci, PCI_IO_BASE_UPPER16, 2, io_base);
+ cns3xxx_write_config(cnspci, PCI_IO_LIMIT_UPPER16, 2, io_limit);
+
+ if (!cnspci->linked)
+ return;
+
+ /* Set Device Max_Read_Request_Size to 128 byte */
+ pcie_bus_config = PCIE_BUS_PEER2PEER;
+
+ /* Disable PCIe0 Interrupt Mask INTA to INTD */
+ __raw_writel(~0x3FFF, MISC_PCIE_INT_MASK(cnspci->port));
+}
+
+static int cns3xxx_pcie_abort_handler(unsigned long addr, unsigned int fsr,
+ struct pt_regs *regs)
+{
+ if (fsr & (1 << 10))
+ regs->ARM_pc += 4;
+ return 0;
+}
+
+void __init cns3xxx_pcie_init_late(void)
+{
+ int i;
+ void *private_data;
+ struct hw_pci hw_pci = {
+ .nr_controllers = 1,
+ .ops = &cns3xxx_pcie_ops,
+ .setup = cns3xxx_pci_setup,
+ .map_irq = cns3xxx_pcie_map_irq,
+ .private_data = &private_data,
+ };
+
+ pcibios_min_io = 0;
+ pcibios_min_mem = 0;
+
+ hook_fault_code(16 + 6, cns3xxx_pcie_abort_handler, SIGBUS, 0,
+ "imprecise external abort");
+
+ for (i = 0; i < ARRAY_SIZE(cns3xxx_pcie); i++) {
+ cns3xxx_pwr_clk_en(0x1 << PM_CLK_GATE_REG_OFFSET_PCIE(i));
+ cns3xxx_pwr_soft_rst(0x1 << PM_SOFT_RST_REG_OFFST_PCIE(i));
+ cns3xxx_pcie_check_link(&cns3xxx_pcie[i]);
+ cns3xxx_pcie_hw_init(&cns3xxx_pcie[i]);
+ private_data = &cns3xxx_pcie[i];
+ pci_common_init(&hw_pci);
+ }
+
+ pci_assign_unassigned_resources();
+}