diff options
Diffstat (limited to 'drivers/pci/controller/pci-mvebu.c')
| -rw-r--r-- | drivers/pci/controller/pci-mvebu.c | 1737 |
1 files changed, 1737 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c new file mode 100644 index 000000000..29fe09c99 --- /dev/null +++ b/drivers/pci/controller/pci-mvebu.c @@ -0,0 +1,1737 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe driver for Marvell Armada 370 and Armada XP SoCs + * + * Author: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/init.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/mbus.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_pci.h> +#include <linux/of_platform.h> + +#include "../pci.h" +#include "../pci-bridge-emul.h" + +/* + * PCIe unit register offsets. + */ +#define PCIE_DEV_ID_OFF 0x0000 +#define PCIE_CMD_OFF 0x0004 +#define PCIE_DEV_REV_OFF 0x0008 +#define PCIE_BAR_LO_OFF(n) (0x0010 + ((n) << 3)) +#define PCIE_BAR_HI_OFF(n) (0x0014 + ((n) << 3)) +#define PCIE_SSDEV_ID_OFF 0x002c +#define PCIE_CAP_PCIEXP 0x0060 +#define PCIE_CAP_PCIERR_OFF 0x0100 +#define PCIE_BAR_CTRL_OFF(n) (0x1804 + (((n) - 1) * 4)) +#define PCIE_WIN04_CTRL_OFF(n) (0x1820 + ((n) << 4)) +#define PCIE_WIN04_BASE_OFF(n) (0x1824 + ((n) << 4)) +#define PCIE_WIN04_REMAP_OFF(n) (0x182c + ((n) << 4)) +#define PCIE_WIN5_CTRL_OFF 0x1880 +#define PCIE_WIN5_BASE_OFF 0x1884 +#define PCIE_WIN5_REMAP_OFF 0x188c +#define PCIE_CONF_ADDR_OFF 0x18f8 +#define PCIE_CONF_ADDR_EN 0x80000000 +#define PCIE_CONF_REG(r) ((((r) & 0xf00) << 16) | ((r) & 0xfc)) +#define PCIE_CONF_BUS(b) (((b) & 0xff) << 16) +#define PCIE_CONF_DEV(d) (((d) & 0x1f) << 11) +#define PCIE_CONF_FUNC(f) (((f) & 0x7) << 8) +#define PCIE_CONF_ADDR(bus, devfn, where) \ + (PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn)) | \ + PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \ + PCIE_CONF_ADDR_EN) +#define PCIE_CONF_DATA_OFF 0x18fc +#define PCIE_INT_CAUSE_OFF 0x1900 +#define PCIE_INT_UNMASK_OFF 0x1910 +#define PCIE_INT_INTX(i) BIT(24+i) +#define PCIE_INT_PM_PME BIT(28) +#define PCIE_INT_ALL_MASK GENMASK(31, 0) +#define PCIE_CTRL_OFF 0x1a00 +#define PCIE_CTRL_X1_MODE 0x0001 +#define PCIE_CTRL_RC_MODE BIT(1) +#define PCIE_CTRL_MASTER_HOT_RESET BIT(24) +#define PCIE_STAT_OFF 0x1a04 +#define PCIE_STAT_BUS 0xff00 +#define PCIE_STAT_DEV 0x1f0000 +#define PCIE_STAT_LINK_DOWN BIT(0) +#define PCIE_SSPL_OFF 0x1a0c +#define PCIE_SSPL_VALUE_SHIFT 0 +#define PCIE_SSPL_VALUE_MASK GENMASK(7, 0) +#define PCIE_SSPL_SCALE_SHIFT 8 +#define PCIE_SSPL_SCALE_MASK GENMASK(9, 8) +#define PCIE_SSPL_ENABLE BIT(16) +#define PCIE_RC_RTSTA 0x1a14 +#define PCIE_DEBUG_CTRL 0x1a60 +#define PCIE_DEBUG_SOFT_RESET BIT(20) + +struct mvebu_pcie_port; + +/* Structure representing all PCIe interfaces */ +struct mvebu_pcie { + struct platform_device *pdev; + struct mvebu_pcie_port *ports; + struct resource io; + struct resource realio; + struct resource mem; + int nports; +}; + +struct mvebu_pcie_window { + phys_addr_t base; + phys_addr_t remap; + size_t size; +}; + +/* Structure representing one PCIe interface */ +struct mvebu_pcie_port { + char *name; + void __iomem *base; + u32 port; + u32 lane; + bool is_x4; + int devfn; + unsigned int mem_target; + unsigned int mem_attr; + unsigned int io_target; + unsigned int io_attr; + struct clk *clk; + struct gpio_desc *reset_gpio; + char *reset_name; + struct pci_bridge_emul bridge; + struct device_node *dn; + struct mvebu_pcie *pcie; + struct mvebu_pcie_window memwin; + struct mvebu_pcie_window iowin; + u32 saved_pcie_stat; + struct resource regs; + u8 slot_power_limit_value; + u8 slot_power_limit_scale; + struct irq_domain *intx_irq_domain; + raw_spinlock_t irq_lock; + int intx_irq; +}; + +static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg) +{ + writel(val, port->base + reg); +} + +static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg) +{ + return readl(port->base + reg); +} + +static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port) +{ + return port->io_target != -1 && port->io_attr != -1; +} + +static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port) +{ + return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN); +} + +static u8 mvebu_pcie_get_local_bus_nr(struct mvebu_pcie_port *port) +{ + return (mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_BUS) >> 8; +} + +static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr) +{ + u32 stat; + + stat = mvebu_readl(port, PCIE_STAT_OFF); + stat &= ~PCIE_STAT_BUS; + stat |= nr << 8; + mvebu_writel(port, stat, PCIE_STAT_OFF); +} + +static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr) +{ + u32 stat; + + stat = mvebu_readl(port, PCIE_STAT_OFF); + stat &= ~PCIE_STAT_DEV; + stat |= nr << 16; + mvebu_writel(port, stat, PCIE_STAT_OFF); +} + +static void mvebu_pcie_disable_wins(struct mvebu_pcie_port *port) +{ + int i; + + mvebu_writel(port, 0, PCIE_BAR_LO_OFF(0)); + mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0)); + + for (i = 1; i < 3; i++) { + mvebu_writel(port, 0, PCIE_BAR_CTRL_OFF(i)); + mvebu_writel(port, 0, PCIE_BAR_LO_OFF(i)); + mvebu_writel(port, 0, PCIE_BAR_HI_OFF(i)); + } + + for (i = 0; i < 5; i++) { + mvebu_writel(port, 0, PCIE_WIN04_CTRL_OFF(i)); + mvebu_writel(port, 0, PCIE_WIN04_BASE_OFF(i)); + mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i)); + } + + mvebu_writel(port, 0, PCIE_WIN5_CTRL_OFF); + mvebu_writel(port, 0, PCIE_WIN5_BASE_OFF); + mvebu_writel(port, 0, PCIE_WIN5_REMAP_OFF); +} + +/* + * Setup PCIE BARs and Address Decode Wins: + * BAR[0] -> internal registers (needed for MSI) + * BAR[1] -> covers all DRAM banks + * BAR[2] -> Disabled + * WIN[0-3] -> DRAM bank[0-3] + */ +static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port) +{ + const struct mbus_dram_target_info *dram; + u32 size; + int i; + + dram = mv_mbus_dram_info(); + + /* First, disable and clear BARs and windows. */ + mvebu_pcie_disable_wins(port); + + /* Setup windows for DDR banks. Count total DDR size on the fly. */ + size = 0; + for (i = 0; i < dram->num_cs; i++) { + const struct mbus_dram_window *cs = dram->cs + i; + + mvebu_writel(port, cs->base & 0xffff0000, + PCIE_WIN04_BASE_OFF(i)); + mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i)); + mvebu_writel(port, + ((cs->size - 1) & 0xffff0000) | + (cs->mbus_attr << 8) | + (dram->mbus_dram_target_id << 4) | 1, + PCIE_WIN04_CTRL_OFF(i)); + + size += cs->size; + } + + /* Round up 'size' to the nearest power of two. */ + if ((size & (size - 1)) != 0) + size = 1 << fls(size); + + /* Setup BAR[1] to all DRAM banks. */ + mvebu_writel(port, dram->cs[0].base, PCIE_BAR_LO_OFF(1)); + mvebu_writel(port, 0, PCIE_BAR_HI_OFF(1)); + mvebu_writel(port, ((size - 1) & 0xffff0000) | 1, + PCIE_BAR_CTRL_OFF(1)); + + /* + * Point BAR[0] to the device's internal registers. + */ + mvebu_writel(port, round_down(port->regs.start, SZ_1M), PCIE_BAR_LO_OFF(0)); + mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0)); +} + +static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port) +{ + u32 ctrl, lnkcap, cmd, dev_rev, unmask, sspl; + + /* Setup PCIe controller to Root Complex mode. */ + ctrl = mvebu_readl(port, PCIE_CTRL_OFF); + ctrl |= PCIE_CTRL_RC_MODE; + mvebu_writel(port, ctrl, PCIE_CTRL_OFF); + + /* + * Set Maximum Link Width to X1 or X4 in Root Port's PCIe Link + * Capability register. This register is defined by PCIe specification + * as read-only but this mvebu controller has it as read-write and must + * be set to number of SerDes PCIe lanes (1 or 4). If this register is + * not set correctly then link with endpoint card is not established. + */ + lnkcap = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP); + lnkcap &= ~PCI_EXP_LNKCAP_MLW; + lnkcap |= FIELD_PREP(PCI_EXP_LNKCAP_MLW, port->is_x4 ? 4 : 1); + mvebu_writel(port, lnkcap, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP); + + /* Disable Root Bridge I/O space, memory space and bus mastering. */ + cmd = mvebu_readl(port, PCIE_CMD_OFF); + cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER); + mvebu_writel(port, cmd, PCIE_CMD_OFF); + + /* + * Change Class Code of PCI Bridge device to PCI Bridge (0x6004) + * because default value is Memory controller (0x5080). + * + * Note that this mvebu PCI Bridge does not have compliant Type 1 + * Configuration Space. Header Type is reported as Type 0 and it + * has format of Type 0 config space. + * + * Moreover Type 0 BAR registers (ranges 0x10 - 0x28 and 0x30 - 0x34) + * have the same format in Marvell's specification as in PCIe + * specification, but their meaning is totally different and they do + * different things: they are aliased into internal mvebu registers + * (e.g. PCIE_BAR_LO_OFF) and these should not be changed or + * reconfigured by pci device drivers. + * + * Therefore driver uses emulation of PCI Bridge which emulates + * access to configuration space via internal mvebu registers or + * emulated configuration buffer. Driver access these PCI Bridge + * directly for simplification, but these registers can be accessed + * also via standard mvebu way for accessing PCI config space. + */ + dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF); + dev_rev &= ~0xffffff00; + dev_rev |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8; + mvebu_writel(port, dev_rev, PCIE_DEV_REV_OFF); + + /* Point PCIe unit MBUS decode windows to DRAM space. */ + mvebu_pcie_setup_wins(port); + + /* + * Program Root Port to automatically send Set_Slot_Power_Limit + * PCIe Message when changing status from Dl_Down to Dl_Up and valid + * slot power limit was specified. + */ + sspl = mvebu_readl(port, PCIE_SSPL_OFF); + sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE); + if (port->slot_power_limit_value) { + sspl |= port->slot_power_limit_value << PCIE_SSPL_VALUE_SHIFT; + sspl |= port->slot_power_limit_scale << PCIE_SSPL_SCALE_SHIFT; + sspl |= PCIE_SSPL_ENABLE; + } + mvebu_writel(port, sspl, PCIE_SSPL_OFF); + + /* Mask all interrupt sources. */ + mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF); + + /* Clear all interrupt causes. */ + mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF); + + /* Check if "intx" interrupt was specified in DT. */ + if (port->intx_irq > 0) + return; + + /* + * Fallback code when "intx" interrupt was not specified in DT: + * Unmask all legacy INTx interrupts as driver does not provide a way + * for masking and unmasking of individual legacy INTx interrupts. + * Legacy INTx are reported via one shared GIC source and therefore + * kernel cannot distinguish which individual legacy INTx was triggered. + * These interrupts are shared, so it should not cause any issue. Just + * performance penalty as every PCIe interrupt handler needs to be + * called when some interrupt is triggered. + */ + unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF); + unmask |= PCIE_INT_INTX(0) | PCIE_INT_INTX(1) | + PCIE_INT_INTX(2) | PCIE_INT_INTX(3); + mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF); +} + +static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie, + struct pci_bus *bus, + int devfn); + +static int mvebu_pcie_child_rd_conf(struct pci_bus *bus, u32 devfn, int where, + int size, u32 *val) +{ + struct mvebu_pcie *pcie = bus->sysdata; + struct mvebu_pcie_port *port; + void __iomem *conf_data; + + port = mvebu_pcie_find_port(pcie, bus, devfn); + if (!port) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (!mvebu_pcie_link_up(port)) + return PCIBIOS_DEVICE_NOT_FOUND; + + conf_data = port->base + PCIE_CONF_DATA_OFF; + + mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where), + PCIE_CONF_ADDR_OFF); + + switch (size) { + case 1: + *val = readb_relaxed(conf_data + (where & 3)); + break; + case 2: + *val = readw_relaxed(conf_data + (where & 2)); + break; + case 4: + *val = readl_relaxed(conf_data); + break; + default: + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + return PCIBIOS_SUCCESSFUL; +} + +static int mvebu_pcie_child_wr_conf(struct pci_bus *bus, u32 devfn, + int where, int size, u32 val) +{ + struct mvebu_pcie *pcie = bus->sysdata; + struct mvebu_pcie_port *port; + void __iomem *conf_data; + + port = mvebu_pcie_find_port(pcie, bus, devfn); + if (!port) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (!mvebu_pcie_link_up(port)) + return PCIBIOS_DEVICE_NOT_FOUND; + + conf_data = port->base + PCIE_CONF_DATA_OFF; + + mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where), + PCIE_CONF_ADDR_OFF); + + switch (size) { + case 1: + writeb(val, conf_data + (where & 3)); + break; + case 2: + writew(val, conf_data + (where & 2)); + break; + case 4: + writel(val, conf_data); + break; + default: + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + return PCIBIOS_SUCCESSFUL; +} + +static struct pci_ops mvebu_pcie_child_ops = { + .read = mvebu_pcie_child_rd_conf, + .write = mvebu_pcie_child_wr_conf, +}; + +/* + * Remove windows, starting from the largest ones to the smallest + * ones. + */ +static void mvebu_pcie_del_windows(struct mvebu_pcie_port *port, + phys_addr_t base, size_t size) +{ + while (size) { + size_t sz = 1 << (fls(size) - 1); + + mvebu_mbus_del_window(base, sz); + base += sz; + size -= sz; + } +} + +/* + * MBus windows can only have a power of two size, but PCI BARs do not + * have this constraint. Therefore, we have to split the PCI BAR into + * areas each having a power of two size. We start from the largest + * one (i.e highest order bit set in the size). + */ +static int mvebu_pcie_add_windows(struct mvebu_pcie_port *port, + unsigned int target, unsigned int attribute, + phys_addr_t base, size_t size, + phys_addr_t remap) +{ + size_t size_mapped = 0; + + while (size) { + size_t sz = 1 << (fls(size) - 1); + int ret; + + ret = mvebu_mbus_add_window_remap_by_id(target, attribute, base, + sz, remap); + if (ret) { + phys_addr_t end = base + sz - 1; + + dev_err(&port->pcie->pdev->dev, + "Could not create MBus window at [mem %pa-%pa]: %d\n", + &base, &end, ret); + mvebu_pcie_del_windows(port, base - size_mapped, + size_mapped); + return ret; + } + + size -= sz; + size_mapped += sz; + base += sz; + if (remap != MVEBU_MBUS_NO_REMAP) + remap += sz; + } + + return 0; +} + +static int mvebu_pcie_set_window(struct mvebu_pcie_port *port, + unsigned int target, unsigned int attribute, + const struct mvebu_pcie_window *desired, + struct mvebu_pcie_window *cur) +{ + int ret; + + if (desired->base == cur->base && desired->remap == cur->remap && + desired->size == cur->size) + return 0; + + if (cur->size != 0) { + mvebu_pcie_del_windows(port, cur->base, cur->size); + cur->size = 0; + cur->base = 0; + + /* + * If something tries to change the window while it is enabled + * the change will not be done atomically. That would be + * difficult to do in the general case. + */ + } + + if (desired->size == 0) + return 0; + + ret = mvebu_pcie_add_windows(port, target, attribute, desired->base, + desired->size, desired->remap); + if (ret) { + cur->size = 0; + cur->base = 0; + return ret; + } + + *cur = *desired; + return 0; +} + +static int mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port) +{ + struct mvebu_pcie_window desired = {}; + struct pci_bridge_emul_conf *conf = &port->bridge.conf; + + /* Are the new iobase/iolimit values invalid? */ + if (conf->iolimit < conf->iobase || + le16_to_cpu(conf->iolimitupper) < le16_to_cpu(conf->iobaseupper)) + return mvebu_pcie_set_window(port, port->io_target, port->io_attr, + &desired, &port->iowin); + + /* + * We read the PCI-to-PCI bridge emulated registers, and + * calculate the base address and size of the address decoding + * window to setup, according to the PCI-to-PCI bridge + * specifications. iobase is the bus address, port->iowin_base + * is the CPU address. + */ + desired.remap = ((conf->iobase & 0xF0) << 8) | + (le16_to_cpu(conf->iobaseupper) << 16); + desired.base = port->pcie->io.start + desired.remap; + desired.size = ((0xFFF | ((conf->iolimit & 0xF0) << 8) | + (le16_to_cpu(conf->iolimitupper) << 16)) - + desired.remap) + + 1; + + return mvebu_pcie_set_window(port, port->io_target, port->io_attr, &desired, + &port->iowin); +} + +static int mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port) +{ + struct mvebu_pcie_window desired = {.remap = MVEBU_MBUS_NO_REMAP}; + struct pci_bridge_emul_conf *conf = &port->bridge.conf; + + /* Are the new membase/memlimit values invalid? */ + if (le16_to_cpu(conf->memlimit) < le16_to_cpu(conf->membase)) + return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, + &desired, &port->memwin); + + /* + * We read the PCI-to-PCI bridge emulated registers, and + * calculate the base address and size of the address decoding + * window to setup, according to the PCI-to-PCI bridge + * specifications. + */ + desired.base = ((le16_to_cpu(conf->membase) & 0xFFF0) << 16); + desired.size = (((le16_to_cpu(conf->memlimit) & 0xFFF0) << 16) | 0xFFFFF) - + desired.base + 1; + + return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, &desired, + &port->memwin); +} + +static pci_bridge_emul_read_status_t +mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge, + int reg, u32 *value) +{ + struct mvebu_pcie_port *port = bridge->data; + + switch (reg) { + case PCI_COMMAND: + *value = mvebu_readl(port, PCIE_CMD_OFF); + break; + + case PCI_PRIMARY_BUS: { + /* + * From the whole 32bit register we support reading from HW only + * secondary bus number which is mvebu local bus number. + * Other bits are retrieved only from emulated config buffer. + */ + __le32 *cfgspace = (__le32 *)&bridge->conf; + u32 val = le32_to_cpu(cfgspace[PCI_PRIMARY_BUS / 4]); + val &= ~0xff00; + val |= mvebu_pcie_get_local_bus_nr(port) << 8; + *value = val; + break; + } + + case PCI_INTERRUPT_LINE: { + /* + * From the whole 32bit register we support reading from HW only + * one bit: PCI_BRIDGE_CTL_BUS_RESET. + * Other bits are retrieved only from emulated config buffer. + */ + __le32 *cfgspace = (__le32 *)&bridge->conf; + u32 val = le32_to_cpu(cfgspace[PCI_INTERRUPT_LINE / 4]); + if (mvebu_readl(port, PCIE_CTRL_OFF) & PCIE_CTRL_MASTER_HOT_RESET) + val |= PCI_BRIDGE_CTL_BUS_RESET << 16; + else + val &= ~(PCI_BRIDGE_CTL_BUS_RESET << 16); + *value = val; + break; + } + + default: + return PCI_BRIDGE_EMUL_NOT_HANDLED; + } + + return PCI_BRIDGE_EMUL_HANDLED; +} + +static pci_bridge_emul_read_status_t +mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, + int reg, u32 *value) +{ + struct mvebu_pcie_port *port = bridge->data; + + switch (reg) { + case PCI_EXP_DEVCAP: + *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP); + break; + + case PCI_EXP_DEVCTL: + *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL); + break; + + case PCI_EXP_LNKCAP: + /* + * PCIe requires that the Clock Power Management capability bit + * is hard-wired to zero for downstream ports but HW returns 1. + * Additionally enable Data Link Layer Link Active Reporting + * Capable bit as DL_Active indication is provided too. + */ + *value = (mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) & + ~PCI_EXP_LNKCAP_CLKPM) | PCI_EXP_LNKCAP_DLLLARC; + break; + + case PCI_EXP_LNKCTL: + /* DL_Active indication is provided via PCIE_STAT_OFF */ + *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL) | + (mvebu_pcie_link_up(port) ? + (PCI_EXP_LNKSTA_DLLLA << 16) : 0); + break; + + case PCI_EXP_SLTCTL: { + u16 slotctl = le16_to_cpu(bridge->pcie_conf.slotctl); + u16 slotsta = le16_to_cpu(bridge->pcie_conf.slotsta); + u32 val = 0; + /* + * When slot power limit was not specified in DT then + * ASPL_DISABLE bit is stored only in emulated config space. + * Otherwise reflect status of PCIE_SSPL_ENABLE bit in HW. + */ + if (!port->slot_power_limit_value) + val |= slotctl & PCI_EXP_SLTCTL_ASPL_DISABLE; + else if (!(mvebu_readl(port, PCIE_SSPL_OFF) & PCIE_SSPL_ENABLE)) + val |= PCI_EXP_SLTCTL_ASPL_DISABLE; + /* This callback is 32-bit and in high bits is slot status. */ + val |= slotsta << 16; + *value = val; + break; + } + + case PCI_EXP_RTSTA: + *value = mvebu_readl(port, PCIE_RC_RTSTA); + break; + + case PCI_EXP_DEVCAP2: + *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP2); + break; + + case PCI_EXP_DEVCTL2: + *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2); + break; + + case PCI_EXP_LNKCTL2: + *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2); + break; + + default: + return PCI_BRIDGE_EMUL_NOT_HANDLED; + } + + return PCI_BRIDGE_EMUL_HANDLED; +} + +static pci_bridge_emul_read_status_t +mvebu_pci_bridge_emul_ext_conf_read(struct pci_bridge_emul *bridge, + int reg, u32 *value) +{ + struct mvebu_pcie_port *port = bridge->data; + + switch (reg) { + case 0: + case PCI_ERR_UNCOR_STATUS: + case PCI_ERR_UNCOR_MASK: + case PCI_ERR_UNCOR_SEVER: + case PCI_ERR_COR_STATUS: + case PCI_ERR_COR_MASK: + case PCI_ERR_CAP: + case PCI_ERR_HEADER_LOG+0: + case PCI_ERR_HEADER_LOG+4: + case PCI_ERR_HEADER_LOG+8: + case PCI_ERR_HEADER_LOG+12: + case PCI_ERR_ROOT_COMMAND: + case PCI_ERR_ROOT_STATUS: + case PCI_ERR_ROOT_ERR_SRC: + *value = mvebu_readl(port, PCIE_CAP_PCIERR_OFF + reg); + break; + + default: + return PCI_BRIDGE_EMUL_NOT_HANDLED; + } + + return PCI_BRIDGE_EMUL_HANDLED; +} + +static void +mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge, + int reg, u32 old, u32 new, u32 mask) +{ + struct mvebu_pcie_port *port = bridge->data; + struct pci_bridge_emul_conf *conf = &bridge->conf; + + switch (reg) { + case PCI_COMMAND: + mvebu_writel(port, new, PCIE_CMD_OFF); + break; + + case PCI_IO_BASE: + if ((mask & 0xffff) && mvebu_has_ioport(port) && + mvebu_pcie_handle_iobase_change(port)) { + /* On error disable IO range */ + conf->iobase &= ~0xf0; + conf->iolimit &= ~0xf0; + conf->iobase |= 0xf0; + conf->iobaseupper = cpu_to_le16(0x0000); + conf->iolimitupper = cpu_to_le16(0x0000); + } + break; + + case PCI_MEMORY_BASE: + if (mvebu_pcie_handle_membase_change(port)) { + /* On error disable mem range */ + conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) & ~0xfff0); + conf->memlimit = cpu_to_le16(le16_to_cpu(conf->memlimit) & ~0xfff0); + conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) | 0xfff0); + } + break; + + case PCI_IO_BASE_UPPER16: + if (mvebu_has_ioport(port) && + mvebu_pcie_handle_iobase_change(port)) { + /* On error disable IO range */ + conf->iobase &= ~0xf0; + conf->iolimit &= ~0xf0; + conf->iobase |= 0xf0; + conf->iobaseupper = cpu_to_le16(0x0000); + conf->iolimitupper = cpu_to_le16(0x0000); + } + break; + + case PCI_PRIMARY_BUS: + if (mask & 0xff00) + mvebu_pcie_set_local_bus_nr(port, conf->secondary_bus); + break; + + case PCI_INTERRUPT_LINE: + if (mask & (PCI_BRIDGE_CTL_BUS_RESET << 16)) { + u32 ctrl = mvebu_readl(port, PCIE_CTRL_OFF); + if (new & (PCI_BRIDGE_CTL_BUS_RESET << 16)) + ctrl |= PCIE_CTRL_MASTER_HOT_RESET; + else + ctrl &= ~PCIE_CTRL_MASTER_HOT_RESET; + mvebu_writel(port, ctrl, PCIE_CTRL_OFF); + } + break; + + default: + break; + } +} + +static void +mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge, + int reg, u32 old, u32 new, u32 mask) +{ + struct mvebu_pcie_port *port = bridge->data; + + switch (reg) { + case PCI_EXP_DEVCTL: + mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL); + break; + + case PCI_EXP_LNKCTL: + /* + * PCIe requires that the Enable Clock Power Management bit + * is hard-wired to zero for downstream ports but HW allows + * to change it. + */ + new &= ~PCI_EXP_LNKCTL_CLKREQ_EN; + + mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL); + break; + + case PCI_EXP_SLTCTL: + /* + * Allow to change PCIE_SSPL_ENABLE bit only when slot power + * limit was specified in DT and configured into HW. + */ + if ((mask & PCI_EXP_SLTCTL_ASPL_DISABLE) && + port->slot_power_limit_value) { + u32 sspl = mvebu_readl(port, PCIE_SSPL_OFF); + if (new & PCI_EXP_SLTCTL_ASPL_DISABLE) + sspl &= ~PCIE_SSPL_ENABLE; + else + sspl |= PCIE_SSPL_ENABLE; + mvebu_writel(port, sspl, PCIE_SSPL_OFF); + } + break; + + case PCI_EXP_RTSTA: + /* + * PME Status bit in Root Status Register (PCIE_RC_RTSTA) + * is read-only and can be cleared only by writing 0b to the + * Interrupt Cause RW0C register (PCIE_INT_CAUSE_OFF). So + * clear PME via Interrupt Cause. + */ + if (new & PCI_EXP_RTSTA_PME) + mvebu_writel(port, ~PCIE_INT_PM_PME, PCIE_INT_CAUSE_OFF); + break; + + case PCI_EXP_DEVCTL2: + mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2); + break; + + case PCI_EXP_LNKCTL2: + mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2); + break; + + default: + break; + } +} + +static void +mvebu_pci_bridge_emul_ext_conf_write(struct pci_bridge_emul *bridge, + int reg, u32 old, u32 new, u32 mask) +{ + struct mvebu_pcie_port *port = bridge->data; + + switch (reg) { + /* These are W1C registers, so clear other bits */ + case PCI_ERR_UNCOR_STATUS: + case PCI_ERR_COR_STATUS: + case PCI_ERR_ROOT_STATUS: + new &= mask; + fallthrough; + + case PCI_ERR_UNCOR_MASK: + case PCI_ERR_UNCOR_SEVER: + case PCI_ERR_COR_MASK: + case PCI_ERR_CAP: + case PCI_ERR_HEADER_LOG+0: + case PCI_ERR_HEADER_LOG+4: + case PCI_ERR_HEADER_LOG+8: + case PCI_ERR_HEADER_LOG+12: + case PCI_ERR_ROOT_COMMAND: + case PCI_ERR_ROOT_ERR_SRC: + mvebu_writel(port, new, PCIE_CAP_PCIERR_OFF + reg); + break; + + default: + break; + } +} + +static const struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = { + .read_base = mvebu_pci_bridge_emul_base_conf_read, + .write_base = mvebu_pci_bridge_emul_base_conf_write, + .read_pcie = mvebu_pci_bridge_emul_pcie_conf_read, + .write_pcie = mvebu_pci_bridge_emul_pcie_conf_write, + .read_ext = mvebu_pci_bridge_emul_ext_conf_read, + .write_ext = mvebu_pci_bridge_emul_ext_conf_write, +}; + +/* + * Initialize the configuration space of the PCI-to-PCI bridge + * associated with the given PCIe interface. + */ +static int mvebu_pci_bridge_emul_init(struct mvebu_pcie_port *port) +{ + unsigned int bridge_flags = PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD; + struct pci_bridge_emul *bridge = &port->bridge; + u32 dev_id = mvebu_readl(port, PCIE_DEV_ID_OFF); + u32 dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF); + u32 ssdev_id = mvebu_readl(port, PCIE_SSDEV_ID_OFF); + u32 pcie_cap = mvebu_readl(port, PCIE_CAP_PCIEXP); + u8 pcie_cap_ver = ((pcie_cap >> 16) & PCI_EXP_FLAGS_VERS); + + bridge->conf.vendor = cpu_to_le16(dev_id & 0xffff); + bridge->conf.device = cpu_to_le16(dev_id >> 16); + bridge->conf.class_revision = cpu_to_le32(dev_rev & 0xff); + + if (mvebu_has_ioport(port)) { + /* We support 32 bits I/O addressing */ + bridge->conf.iobase = PCI_IO_RANGE_TYPE_32; + bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32; + } else { + bridge_flags |= PCI_BRIDGE_EMUL_NO_IO_FORWARD; + } + + /* + * Older mvebu hardware provides PCIe Capability structure only in + * version 1. New hardware provides it in version 2. + * Enable slot support which is emulated. + */ + bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver | PCI_EXP_FLAGS_SLOT); + + /* + * Set Presence Detect State bit permanently as there is no support for + * unplugging PCIe card from the slot. Assume that PCIe card is always + * connected in slot. + * + * Set physical slot number to port+1 as mvebu ports are indexed from + * zero and zero value is reserved for ports within the same silicon + * as Root Port which is not mvebu case. + * + * Also set correct slot power limit. + */ + bridge->pcie_conf.slotcap = cpu_to_le32( + FIELD_PREP(PCI_EXP_SLTCAP_SPLV, port->slot_power_limit_value) | + FIELD_PREP(PCI_EXP_SLTCAP_SPLS, port->slot_power_limit_scale) | + FIELD_PREP(PCI_EXP_SLTCAP_PSN, port->port+1)); + bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS); + + bridge->subsystem_vendor_id = ssdev_id & 0xffff; + bridge->subsystem_id = ssdev_id >> 16; + bridge->has_pcie = true; + bridge->pcie_start = PCIE_CAP_PCIEXP; + bridge->data = port; + bridge->ops = &mvebu_pci_bridge_emul_ops; + + return pci_bridge_emul_init(bridge, bridge_flags); +} + +static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys) +{ + return sys->private_data; +} + +static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie, + struct pci_bus *bus, + int devfn) +{ + int i; + + for (i = 0; i < pcie->nports; i++) { + struct mvebu_pcie_port *port = &pcie->ports[i]; + + if (!port->base) + continue; + + if (bus->number == 0 && port->devfn == devfn) + return port; + if (bus->number != 0 && + bus->number >= port->bridge.conf.secondary_bus && + bus->number <= port->bridge.conf.subordinate_bus) + return port; + } + + return NULL; +} + +/* PCI configuration space write function */ +static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn, + int where, int size, u32 val) +{ + struct mvebu_pcie *pcie = bus->sysdata; + struct mvebu_pcie_port *port; + + port = mvebu_pcie_find_port(pcie, bus, devfn); + if (!port) + return PCIBIOS_DEVICE_NOT_FOUND; + + return pci_bridge_emul_conf_write(&port->bridge, where, size, val); +} + +/* PCI configuration space read function */ +static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, + int size, u32 *val) +{ + struct mvebu_pcie *pcie = bus->sysdata; + struct mvebu_pcie_port *port; + + port = mvebu_pcie_find_port(pcie, bus, devfn); + if (!port) + return PCIBIOS_DEVICE_NOT_FOUND; + + return pci_bridge_emul_conf_read(&port->bridge, where, size, val); +} + +static struct pci_ops mvebu_pcie_ops = { + .read = mvebu_pcie_rd_conf, + .write = mvebu_pcie_wr_conf, +}; + +static void mvebu_pcie_intx_irq_mask(struct irq_data *d) +{ + struct mvebu_pcie_port *port = d->domain->host_data; + irq_hw_number_t hwirq = irqd_to_hwirq(d); + unsigned long flags; + u32 unmask; + + raw_spin_lock_irqsave(&port->irq_lock, flags); + unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF); + unmask &= ~PCIE_INT_INTX(hwirq); + mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF); + raw_spin_unlock_irqrestore(&port->irq_lock, flags); +} + +static void mvebu_pcie_intx_irq_unmask(struct irq_data *d) +{ + struct mvebu_pcie_port *port = d->domain->host_data; + irq_hw_number_t hwirq = irqd_to_hwirq(d); + unsigned long flags; + u32 unmask; + + raw_spin_lock_irqsave(&port->irq_lock, flags); + unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF); + unmask |= PCIE_INT_INTX(hwirq); + mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF); + raw_spin_unlock_irqrestore(&port->irq_lock, flags); +} + +static struct irq_chip intx_irq_chip = { + .name = "mvebu-INTx", + .irq_mask = mvebu_pcie_intx_irq_mask, + .irq_unmask = mvebu_pcie_intx_irq_unmask, +}; + +static int mvebu_pcie_intx_irq_map(struct irq_domain *h, + unsigned int virq, irq_hw_number_t hwirq) +{ + struct mvebu_pcie_port *port = h->host_data; + + irq_set_status_flags(virq, IRQ_LEVEL); + irq_set_chip_and_handler(virq, &intx_irq_chip, handle_level_irq); + irq_set_chip_data(virq, port); + + return 0; +} + +static const struct irq_domain_ops mvebu_pcie_intx_irq_domain_ops = { + .map = mvebu_pcie_intx_irq_map, + .xlate = irq_domain_xlate_onecell, +}; + +static int mvebu_pcie_init_irq_domain(struct mvebu_pcie_port *port) +{ + struct device *dev = &port->pcie->pdev->dev; + struct device_node *pcie_intc_node; + + raw_spin_lock_init(&port->irq_lock); + + pcie_intc_node = of_get_next_child(port->dn, NULL); + if (!pcie_intc_node) { + dev_err(dev, "No PCIe Intc node found for %s\n", port->name); + return -ENODEV; + } + + port->intx_irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX, + &mvebu_pcie_intx_irq_domain_ops, + port); + of_node_put(pcie_intc_node); + if (!port->intx_irq_domain) { + dev_err(dev, "Failed to get INTx IRQ domain for %s\n", port->name); + return -ENOMEM; + } + + return 0; +} + +static void mvebu_pcie_irq_handler(struct irq_desc *desc) +{ + struct mvebu_pcie_port *port = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + struct device *dev = &port->pcie->pdev->dev; + u32 cause, unmask, status; + int i; + + chained_irq_enter(chip, desc); + + cause = mvebu_readl(port, PCIE_INT_CAUSE_OFF); + unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF); + status = cause & unmask; + + /* Process legacy INTx interrupts */ + for (i = 0; i < PCI_NUM_INTX; i++) { + if (!(status & PCIE_INT_INTX(i))) + continue; + + if (generic_handle_domain_irq(port->intx_irq_domain, i) == -EINVAL) + dev_err_ratelimited(dev, "unexpected INT%c IRQ\n", (char)i+'A'); + } + + chained_irq_exit(chip, desc); +} + +static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) +{ + /* Interrupt support on mvebu emulated bridges is not implemented yet */ + if (dev->bus->number == 0) + return 0; /* Proper return code 0 == NO_IRQ */ + + return of_irq_parse_and_map_pci(dev, slot, pin); +} + +static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev, + const struct resource *res, + resource_size_t start, + resource_size_t size, + resource_size_t align) +{ + if (dev->bus->number != 0) + return start; + + /* + * On the PCI-to-PCI bridge side, the I/O windows must have at + * least a 64 KB size and the memory windows must have at + * least a 1 MB size. Moreover, MBus windows need to have a + * base address aligned on their size, and their size must be + * a power of two. This means that if the BAR doesn't have a + * power of two size, several MBus windows will actually be + * created. We need to ensure that the biggest MBus window + * (which will be the first one) is aligned on its size, which + * explains the rounddown_pow_of_two() being done here. + */ + if (res->flags & IORESOURCE_IO) + return round_up(start, max_t(resource_size_t, SZ_64K, + rounddown_pow_of_two(size))); + else if (res->flags & IORESOURCE_MEM) + return round_up(start, max_t(resource_size_t, SZ_1M, + rounddown_pow_of_two(size))); + else + return start; +} + +static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev, + struct device_node *np, + struct mvebu_pcie_port *port) +{ + int ret = 0; + + ret = of_address_to_resource(np, 0, &port->regs); + if (ret) + return (void __iomem *)ERR_PTR(ret); + + return devm_ioremap_resource(&pdev->dev, &port->regs); +} + +#define DT_FLAGS_TO_TYPE(flags) (((flags) >> 24) & 0x03) +#define DT_TYPE_IO 0x1 +#define DT_TYPE_MEM32 0x2 +#define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF) +#define DT_CPUADDR_TO_ATTR(cpuaddr) (((cpuaddr) >> 48) & 0xFF) + +static int mvebu_get_tgt_attr(struct device_node *np, int devfn, + unsigned long type, + unsigned int *tgt, + unsigned int *attr) +{ + const int na = 3, ns = 2; + const __be32 *range; + int rlen, nranges, rangesz, pna, i; + + *tgt = -1; + *attr = -1; + + range = of_get_property(np, "ranges", &rlen); + if (!range) + return -EINVAL; + + pna = of_n_addr_cells(np); + rangesz = pna + na + ns; + nranges = rlen / sizeof(__be32) / rangesz; + + for (i = 0; i < nranges; i++, range += rangesz) { + u32 flags = of_read_number(range, 1); + u32 slot = of_read_number(range + 1, 1); + u64 cpuaddr = of_read_number(range + na, pna); + unsigned long rtype; + + if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO) + rtype = IORESOURCE_IO; + else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32) + rtype = IORESOURCE_MEM; + else + continue; + + if (slot == PCI_SLOT(devfn) && type == rtype) { + *tgt = DT_CPUADDR_TO_TARGET(cpuaddr); + *attr = DT_CPUADDR_TO_ATTR(cpuaddr); + return 0; + } + } + + return -ENOENT; +} + +static int mvebu_pcie_suspend(struct device *dev) +{ + struct mvebu_pcie *pcie; + int i; + + pcie = dev_get_drvdata(dev); + for (i = 0; i < pcie->nports; i++) { + struct mvebu_pcie_port *port = pcie->ports + i; + if (!port->base) + continue; + port->saved_pcie_stat = mvebu_readl(port, PCIE_STAT_OFF); + } + + return 0; +} + +static int mvebu_pcie_resume(struct device *dev) +{ + struct mvebu_pcie *pcie; + int i; + + pcie = dev_get_drvdata(dev); + for (i = 0; i < pcie->nports; i++) { + struct mvebu_pcie_port *port = pcie->ports + i; + if (!port->base) + continue; + mvebu_writel(port, port->saved_pcie_stat, PCIE_STAT_OFF); + mvebu_pcie_setup_hw(port); + } + + return 0; +} + +static void mvebu_pcie_port_clk_put(void *data) +{ + struct mvebu_pcie_port *port = data; + + clk_put(port->clk); +} + +static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie, + struct mvebu_pcie_port *port, struct device_node *child) +{ + struct device *dev = &pcie->pdev->dev; + u32 slot_power_limit; + int ret; + u32 num_lanes; + + port->pcie = pcie; + + if (of_property_read_u32(child, "marvell,pcie-port", &port->port)) { + dev_warn(dev, "ignoring %pOF, missing pcie-port property\n", + child); + goto skip; + } + + if (of_property_read_u32(child, "marvell,pcie-lane", &port->lane)) + port->lane = 0; + + if (!of_property_read_u32(child, "num-lanes", &num_lanes) && num_lanes == 4) + port->is_x4 = true; + + port->name = devm_kasprintf(dev, GFP_KERNEL, "pcie%d.%d", port->port, + port->lane); + if (!port->name) { + ret = -ENOMEM; + goto err; + } + + port->devfn = of_pci_get_devfn(child); + if (port->devfn < 0) + goto skip; + if (PCI_FUNC(port->devfn) != 0) { + dev_err(dev, "%s: invalid function number, must be zero\n", + port->name); + goto skip; + } + + ret = mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_MEM, + &port->mem_target, &port->mem_attr); + if (ret < 0) { + dev_err(dev, "%s: cannot get tgt/attr for mem window\n", + port->name); + goto skip; + } + + if (resource_size(&pcie->io) != 0) { + mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_IO, + &port->io_target, &port->io_attr); + } else { + port->io_target = -1; + port->io_attr = -1; + } + + /* + * Old DT bindings do not contain "intx" interrupt + * so do not fail probing driver when interrupt does not exist. + */ + port->intx_irq = of_irq_get_byname(child, "intx"); + if (port->intx_irq == -EPROBE_DEFER) { + ret = port->intx_irq; + goto err; + } + if (port->intx_irq <= 0) { + dev_warn(dev, "%s: legacy INTx interrupts cannot be masked individually, " + "%pOF does not contain intx interrupt\n", + port->name, child); + } + + port->reset_name = devm_kasprintf(dev, GFP_KERNEL, "%s-reset", + port->name); + if (!port->reset_name) { + ret = -ENOMEM; + goto err; + } + + port->reset_gpio = devm_fwnode_gpiod_get(dev, of_fwnode_handle(child), + "reset", GPIOD_OUT_HIGH, + port->name); + ret = PTR_ERR_OR_ZERO(port->reset_gpio); + if (ret) { + if (ret != -ENOENT) + goto err; + /* reset gpio is optional */ + port->reset_gpio = NULL; + devm_kfree(dev, port->reset_name); + port->reset_name = NULL; + } + + slot_power_limit = of_pci_get_slot_power_limit(child, + &port->slot_power_limit_value, + &port->slot_power_limit_scale); + if (slot_power_limit) + dev_info(dev, "%s: Slot power limit %u.%uW\n", + port->name, + slot_power_limit / 1000, + (slot_power_limit / 100) % 10); + + port->clk = of_clk_get_by_name(child, NULL); + if (IS_ERR(port->clk)) { + dev_err(dev, "%s: cannot get clock\n", port->name); + goto skip; + } + + ret = devm_add_action(dev, mvebu_pcie_port_clk_put, port); + if (ret < 0) { + clk_put(port->clk); + goto err; + } + + return 1; + +skip: + ret = 0; + + /* In the case of skipping, we need to free these */ + devm_kfree(dev, port->reset_name); + port->reset_name = NULL; + devm_kfree(dev, port->name); + port->name = NULL; + +err: + return ret; +} + +/* + * Power up a PCIe port. PCIe requires the refclk to be stable for 100µs + * prior to releasing PERST. See table 2-4 in section 2.6.2 AC Specifications + * of the PCI Express Card Electromechanical Specification, 1.1. + */ +static int mvebu_pcie_powerup(struct mvebu_pcie_port *port) +{ + int ret; + + ret = clk_prepare_enable(port->clk); + if (ret < 0) + return ret; + + if (port->reset_gpio) { + u32 reset_udelay = PCI_PM_D3COLD_WAIT * 1000; + + of_property_read_u32(port->dn, "reset-delay-us", + &reset_udelay); + + udelay(100); + + gpiod_set_value_cansleep(port->reset_gpio, 0); + msleep(reset_udelay / 1000); + } + + return 0; +} + +/* + * Power down a PCIe port. Strictly, PCIe requires us to place the card + * in D3hot state before asserting PERST#. + */ +static void mvebu_pcie_powerdown(struct mvebu_pcie_port *port) +{ + gpiod_set_value_cansleep(port->reset_gpio, 1); + + clk_disable_unprepare(port->clk); +} + +/* + * devm_of_pci_get_host_bridge_resources() only sets up translateable resources, + * so we need extra resource setup parsing our special DT properties encoding + * the MEM and IO apertures. + */ +static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie) +{ + struct device *dev = &pcie->pdev->dev; + struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie); + int ret; + + /* Get the PCIe memory aperture */ + mvebu_mbus_get_pcie_mem_aperture(&pcie->mem); + if (resource_size(&pcie->mem) == 0) { + dev_err(dev, "invalid memory aperture size\n"); + return -EINVAL; + } + + pcie->mem.name = "PCI MEM"; + pci_add_resource(&bridge->windows, &pcie->mem); + ret = devm_request_resource(dev, &iomem_resource, &pcie->mem); + if (ret) + return ret; + + /* Get the PCIe IO aperture */ + mvebu_mbus_get_pcie_io_aperture(&pcie->io); + + if (resource_size(&pcie->io) != 0) { + pcie->realio.flags = pcie->io.flags; + pcie->realio.start = PCIBIOS_MIN_IO; + pcie->realio.end = min_t(resource_size_t, + IO_SPACE_LIMIT - SZ_64K, + resource_size(&pcie->io) - 1); + pcie->realio.name = "PCI I/O"; + + ret = devm_pci_remap_iospace(dev, &pcie->realio, pcie->io.start); + if (ret) + return ret; + + pci_add_resource(&bridge->windows, &pcie->realio); + ret = devm_request_resource(dev, &ioport_resource, &pcie->realio); + if (ret) + return ret; + } + + return 0; +} + +static int mvebu_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mvebu_pcie *pcie; + struct pci_host_bridge *bridge; + struct device_node *np = dev->of_node; + struct device_node *child; + int num, i, ret; + + bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct mvebu_pcie)); + if (!bridge) + return -ENOMEM; + + pcie = pci_host_bridge_priv(bridge); + pcie->pdev = pdev; + platform_set_drvdata(pdev, pcie); + + ret = mvebu_pcie_parse_request_resources(pcie); + if (ret) + return ret; + + num = of_get_available_child_count(np); + + pcie->ports = devm_kcalloc(dev, num, sizeof(*pcie->ports), GFP_KERNEL); + if (!pcie->ports) + return -ENOMEM; + + i = 0; + for_each_available_child_of_node(np, child) { + struct mvebu_pcie_port *port = &pcie->ports[i]; + + ret = mvebu_pcie_parse_port(pcie, port, child); + if (ret < 0) { + of_node_put(child); + return ret; + } else if (ret == 0) { + continue; + } + + port->dn = child; + i++; + } + pcie->nports = i; + + for (i = 0; i < pcie->nports; i++) { + struct mvebu_pcie_port *port = &pcie->ports[i]; + int irq = port->intx_irq; + + child = port->dn; + if (!child) + continue; + + ret = mvebu_pcie_powerup(port); + if (ret < 0) + continue; + + port->base = mvebu_pcie_map_registers(pdev, child, port); + if (IS_ERR(port->base)) { + dev_err(dev, "%s: cannot map registers\n", port->name); + port->base = NULL; + mvebu_pcie_powerdown(port); + continue; + } + + ret = mvebu_pci_bridge_emul_init(port); + if (ret < 0) { + dev_err(dev, "%s: cannot init emulated bridge\n", + port->name); + devm_iounmap(dev, port->base); + port->base = NULL; + mvebu_pcie_powerdown(port); + continue; + } + + if (irq > 0) { + ret = mvebu_pcie_init_irq_domain(port); + if (ret) { + dev_err(dev, "%s: cannot init irq domain\n", + port->name); + pci_bridge_emul_cleanup(&port->bridge); + devm_iounmap(dev, port->base); + port->base = NULL; + mvebu_pcie_powerdown(port); + continue; + } + irq_set_chained_handler_and_data(irq, + mvebu_pcie_irq_handler, + port); + } + + /* + * PCIe topology exported by mvebu hw is quite complicated. In + * reality has something like N fully independent host bridges + * where each host bridge has one PCIe Root Port (which acts as + * PCI Bridge device). Each host bridge has its own independent + * internal registers, independent access to PCI config space, + * independent interrupt lines, independent window and memory + * access configuration. But additionally there is some kind of + * peer-to-peer support between PCIe devices behind different + * host bridges limited just to forwarding of memory and I/O + * transactions (forwarding of error messages and config cycles + * is not supported). So we could say there are N independent + * PCIe Root Complexes. + * + * For this kind of setup DT should have been structured into + * N independent PCIe controllers / host bridges. But instead + * structure in past was defined to put PCIe Root Ports of all + * host bridges into one bus zero, like in classic multi-port + * Root Complex setup with just one host bridge. + * + * This means that pci-mvebu.c driver provides "virtual" bus 0 + * on which registers all PCIe Root Ports (PCI Bridge devices) + * specified in DT by their BDF addresses and virtually routes + * PCI config access of each PCI bridge device to specific PCIe + * host bridge. + * + * Normally PCI Bridge should choose between Type 0 and Type 1 + * config requests based on primary and secondary bus numbers + * configured on the bridge itself. But because mvebu PCI Bridge + * does not have registers for primary and secondary bus numbers + * in its config space, it determinates type of config requests + * via its own custom way. + * + * There are two options how mvebu determinate type of config + * request. + * + * 1. If Secondary Bus Number Enable bit is not set or is not + * available (applies for pre-XP PCIe controllers) then Type 0 + * is used if target bus number equals Local Bus Number (bits + * [15:8] in register 0x1a04) and target device number differs + * from Local Device Number (bits [20:16] in register 0x1a04). + * Type 1 is used if target bus number differs from Local Bus + * Number. And when target bus number equals Local Bus Number + * and target device equals Local Device Number then request is + * routed to Local PCI Bridge (PCIe Root Port). + * + * 2. If Secondary Bus Number Enable bit is set (bit 7 in + * register 0x1a2c) then mvebu hw determinate type of config + * request like compliant PCI Bridge based on primary bus number + * which is configured via Local Bus Number (bits [15:8] in + * register 0x1a04) and secondary bus number which is configured + * via Secondary Bus Number (bits [7:0] in register 0x1a2c). + * Local PCI Bridge (PCIe Root Port) is available on primary bus + * as device with Local Device Number (bits [20:16] in register + * 0x1a04). + * + * Secondary Bus Number Enable bit is disabled by default and + * option 2. is not available on pre-XP PCIe controllers. Hence + * this driver always use option 1. + * + * Basically it means that primary and secondary buses shares + * one virtual number configured via Local Bus Number bits and + * Local Device Number bits determinates if accessing primary + * or secondary bus. Set Local Device Number to 1 and redirect + * all writes of PCI Bridge Secondary Bus Number register to + * Local Bus Number (bits [15:8] in register 0x1a04). + * + * So when accessing devices on buses behind secondary bus + * number it would work correctly. And also when accessing + * device 0 at secondary bus number via config space would be + * correctly routed to secondary bus. Due to issues described + * in mvebu_pcie_setup_hw(), PCI Bridges at primary bus (zero) + * are not accessed directly via PCI config space but rarher + * indirectly via kernel emulated PCI bridge driver. + */ + mvebu_pcie_setup_hw(port); + mvebu_pcie_set_local_dev_nr(port, 1); + mvebu_pcie_set_local_bus_nr(port, 0); + } + + bridge->sysdata = pcie; + bridge->ops = &mvebu_pcie_ops; + bridge->child_ops = &mvebu_pcie_child_ops; + bridge->align_resource = mvebu_pcie_align_resource; + bridge->map_irq = mvebu_pcie_map_irq; + + return pci_host_probe(bridge); +} + +static void mvebu_pcie_remove(struct platform_device *pdev) +{ + struct mvebu_pcie *pcie = platform_get_drvdata(pdev); + struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie); + u32 cmd, sspl; + int i; + + /* Remove PCI bus with all devices. */ + pci_lock_rescan_remove(); + pci_stop_root_bus(bridge->bus); + pci_remove_root_bus(bridge->bus); + pci_unlock_rescan_remove(); + + for (i = 0; i < pcie->nports; i++) { + struct mvebu_pcie_port *port = &pcie->ports[i]; + int irq = port->intx_irq; + + if (!port->base) + continue; + + /* Disable Root Bridge I/O space, memory space and bus mastering. */ + cmd = mvebu_readl(port, PCIE_CMD_OFF); + cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER); + mvebu_writel(port, cmd, PCIE_CMD_OFF); + + /* Mask all interrupt sources. */ + mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF); + + /* Clear all interrupt causes. */ + mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF); + + if (irq > 0) + irq_set_chained_handler_and_data(irq, NULL, NULL); + + /* Remove IRQ domains. */ + if (port->intx_irq_domain) + irq_domain_remove(port->intx_irq_domain); + + /* Free config space for emulated root bridge. */ + pci_bridge_emul_cleanup(&port->bridge); + + /* Disable sending Set_Slot_Power_Limit PCIe Message. */ + sspl = mvebu_readl(port, PCIE_SSPL_OFF); + sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE); + mvebu_writel(port, sspl, PCIE_SSPL_OFF); + + /* Disable and clear BARs and windows. */ + mvebu_pcie_disable_wins(port); + + /* Delete PCIe IO and MEM windows. */ + if (port->iowin.size) + mvebu_pcie_del_windows(port, port->iowin.base, port->iowin.size); + if (port->memwin.size) + mvebu_pcie_del_windows(port, port->memwin.base, port->memwin.size); + + /* Power down card and disable clocks. Must be the last step. */ + mvebu_pcie_powerdown(port); + } +} + +static const struct of_device_id mvebu_pcie_of_match_table[] = { + { .compatible = "marvell,armada-xp-pcie", }, + { .compatible = "marvell,armada-370-pcie", }, + { .compatible = "marvell,dove-pcie", }, + { .compatible = "marvell,kirkwood-pcie", }, + {}, +}; + +static const struct dev_pm_ops mvebu_pcie_pm_ops = { + NOIRQ_SYSTEM_SLEEP_PM_OPS(mvebu_pcie_suspend, mvebu_pcie_resume) +}; + +static struct platform_driver mvebu_pcie_driver = { + .driver = { + .name = "mvebu-pcie", + .of_match_table = mvebu_pcie_of_match_table, + .pm = &mvebu_pcie_pm_ops, + }, + .probe = mvebu_pcie_probe, + .remove_new = mvebu_pcie_remove, +}; +module_platform_driver(mvebu_pcie_driver); + +MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@bootlin.com>"); +MODULE_AUTHOR("Pali Rohár <pali@kernel.org>"); +MODULE_DESCRIPTION("Marvell EBU PCIe controller"); +MODULE_LICENSE("GPL v2"); |