diff options
Diffstat (limited to 'drivers/pci/controller/pci-ftpci100.c')
-rw-r--r-- | drivers/pci/controller/pci-ftpci100.c | 551 |
1 files changed, 551 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-ftpci100.c b/drivers/pci/controller/pci-ftpci100.c new file mode 100644 index 000000000..f7e61e169 --- /dev/null +++ b/drivers/pci/controller/pci-ftpci100.c @@ -0,0 +1,551 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for Faraday Technology FTPC100 PCI Controller + * + * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> + * + * Based on the out-of-tree OpenWRT patch for Cortina Gemini: + * Copyright (C) 2009 Janos Laube <janos.dev@gmail.com> + * Copyright (C) 2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt> + * Based on SL2312 PCI controller code + * Storlink (C) 2003 + */ + +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/of_pci.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/irqdomain.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/bitops.h> +#include <linux/irq.h> +#include <linux/clk.h> + +#include "../pci.h" + +/* + * Special configuration registers directly in the first few words + * in I/O space. + */ +#define FTPCI_IOSIZE 0x00 +#define FTPCI_PROT 0x04 /* AHB protection */ +#define FTPCI_CTRL 0x08 /* PCI control signal */ +#define FTPCI_SOFTRST 0x10 /* Soft reset counter and response error enable */ +#define FTPCI_CONFIG 0x28 /* PCI configuration command register */ +#define FTPCI_DATA 0x2C + +#define FARADAY_PCI_STATUS_CMD 0x04 /* Status and command */ +#define FARADAY_PCI_PMC 0x40 /* Power management control */ +#define FARADAY_PCI_PMCSR 0x44 /* Power management status */ +#define FARADAY_PCI_CTRL1 0x48 /* Control register 1 */ +#define FARADAY_PCI_CTRL2 0x4C /* Control register 2 */ +#define FARADAY_PCI_MEM1_BASE_SIZE 0x50 /* Memory base and size #1 */ +#define FARADAY_PCI_MEM2_BASE_SIZE 0x54 /* Memory base and size #2 */ +#define FARADAY_PCI_MEM3_BASE_SIZE 0x58 /* Memory base and size #3 */ + +#define PCI_STATUS_66MHZ_CAPABLE BIT(21) + +/* Bits 31..28 gives INTD..INTA status */ +#define PCI_CTRL2_INTSTS_SHIFT 28 +#define PCI_CTRL2_INTMASK_CMDERR BIT(27) +#define PCI_CTRL2_INTMASK_PARERR BIT(26) +/* Bits 25..22 masks INTD..INTA */ +#define PCI_CTRL2_INTMASK_SHIFT 22 +#define PCI_CTRL2_INTMASK_MABRT_RX BIT(21) +#define PCI_CTRL2_INTMASK_TABRT_RX BIT(20) +#define PCI_CTRL2_INTMASK_TABRT_TX BIT(19) +#define PCI_CTRL2_INTMASK_RETRY4 BIT(18) +#define PCI_CTRL2_INTMASK_SERR_RX BIT(17) +#define PCI_CTRL2_INTMASK_PERR_RX BIT(16) +/* Bit 15 reserved */ +#define PCI_CTRL2_MSTPRI_REQ6 BIT(14) +#define PCI_CTRL2_MSTPRI_REQ5 BIT(13) +#define PCI_CTRL2_MSTPRI_REQ4 BIT(12) +#define PCI_CTRL2_MSTPRI_REQ3 BIT(11) +#define PCI_CTRL2_MSTPRI_REQ2 BIT(10) +#define PCI_CTRL2_MSTPRI_REQ1 BIT(9) +#define PCI_CTRL2_MSTPRI_REQ0 BIT(8) +/* Bits 7..4 reserved */ +/* Bits 3..0 TRDYW */ + +/* + * Memory configs: + * Bit 31..20 defines the PCI side memory base + * Bit 19..16 (4 bits) defines the size per below + */ +#define FARADAY_PCI_MEMBASE_MASK 0xfff00000 +#define FARADAY_PCI_MEMSIZE_1MB 0x0 +#define FARADAY_PCI_MEMSIZE_2MB 0x1 +#define FARADAY_PCI_MEMSIZE_4MB 0x2 +#define FARADAY_PCI_MEMSIZE_8MB 0x3 +#define FARADAY_PCI_MEMSIZE_16MB 0x4 +#define FARADAY_PCI_MEMSIZE_32MB 0x5 +#define FARADAY_PCI_MEMSIZE_64MB 0x6 +#define FARADAY_PCI_MEMSIZE_128MB 0x7 +#define FARADAY_PCI_MEMSIZE_256MB 0x8 +#define FARADAY_PCI_MEMSIZE_512MB 0x9 +#define FARADAY_PCI_MEMSIZE_1GB 0xa +#define FARADAY_PCI_MEMSIZE_2GB 0xb +#define FARADAY_PCI_MEMSIZE_SHIFT 16 + +/* + * The DMA base is set to 0x0 for all memory segments, it reflects the + * fact that the memory of the host system starts at 0x0. + */ +#define FARADAY_PCI_DMA_MEM1_BASE 0x00000000 +#define FARADAY_PCI_DMA_MEM2_BASE 0x00000000 +#define FARADAY_PCI_DMA_MEM3_BASE 0x00000000 + +/** + * struct faraday_pci_variant - encodes IP block differences + * @cascaded_irq: this host has cascaded IRQs from an interrupt controller + * embedded in the host bridge. + */ +struct faraday_pci_variant { + bool cascaded_irq; +}; + +struct faraday_pci { + struct device *dev; + void __iomem *base; + struct irq_domain *irqdomain; + struct pci_bus *bus; + struct clk *bus_clk; +}; + +static int faraday_res_to_memcfg(resource_size_t mem_base, + resource_size_t mem_size, u32 *val) +{ + u32 outval; + + switch (mem_size) { + case SZ_1M: + outval = FARADAY_PCI_MEMSIZE_1MB; + break; + case SZ_2M: + outval = FARADAY_PCI_MEMSIZE_2MB; + break; + case SZ_4M: + outval = FARADAY_PCI_MEMSIZE_4MB; + break; + case SZ_8M: + outval = FARADAY_PCI_MEMSIZE_8MB; + break; + case SZ_16M: + outval = FARADAY_PCI_MEMSIZE_16MB; + break; + case SZ_32M: + outval = FARADAY_PCI_MEMSIZE_32MB; + break; + case SZ_64M: + outval = FARADAY_PCI_MEMSIZE_64MB; + break; + case SZ_128M: + outval = FARADAY_PCI_MEMSIZE_128MB; + break; + case SZ_256M: + outval = FARADAY_PCI_MEMSIZE_256MB; + break; + case SZ_512M: + outval = FARADAY_PCI_MEMSIZE_512MB; + break; + case SZ_1G: + outval = FARADAY_PCI_MEMSIZE_1GB; + break; + case SZ_2G: + outval = FARADAY_PCI_MEMSIZE_2GB; + break; + default: + return -EINVAL; + } + outval <<= FARADAY_PCI_MEMSIZE_SHIFT; + + /* This is probably not good */ + if (mem_base & ~(FARADAY_PCI_MEMBASE_MASK)) + pr_warn("truncated PCI memory base\n"); + /* Translate to bridge side address space */ + outval |= (mem_base & FARADAY_PCI_MEMBASE_MASK); + pr_debug("Translated pci base @%pap, size %pap to config %08x\n", + &mem_base, &mem_size, outval); + + *val = outval; + return 0; +} + +static int faraday_raw_pci_read_config(struct faraday_pci *p, int bus_number, + unsigned int fn, int config, int size, + u32 *value) +{ + writel(PCI_CONF1_ADDRESS(bus_number, PCI_SLOT(fn), + PCI_FUNC(fn), config), + p->base + FTPCI_CONFIG); + + *value = readl(p->base + FTPCI_DATA); + + if (size == 1) + *value = (*value >> (8 * (config & 3))) & 0xFF; + else if (size == 2) + *value = (*value >> (8 * (config & 3))) & 0xFFFF; + + return PCIBIOS_SUCCESSFUL; +} + +static int faraday_pci_read_config(struct pci_bus *bus, unsigned int fn, + int config, int size, u32 *value) +{ + struct faraday_pci *p = bus->sysdata; + + dev_dbg(&bus->dev, + "[read] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n", + PCI_SLOT(fn), PCI_FUNC(fn), config, size, *value); + + return faraday_raw_pci_read_config(p, bus->number, fn, config, size, value); +} + +static int faraday_raw_pci_write_config(struct faraday_pci *p, int bus_number, + unsigned int fn, int config, int size, + u32 value) +{ + int ret = PCIBIOS_SUCCESSFUL; + + writel(PCI_CONF1_ADDRESS(bus_number, PCI_SLOT(fn), + PCI_FUNC(fn), config), + p->base + FTPCI_CONFIG); + + switch (size) { + case 4: + writel(value, p->base + FTPCI_DATA); + break; + case 2: + writew(value, p->base + FTPCI_DATA + (config & 3)); + break; + case 1: + writeb(value, p->base + FTPCI_DATA + (config & 3)); + break; + default: + ret = PCIBIOS_BAD_REGISTER_NUMBER; + } + + return ret; +} + +static int faraday_pci_write_config(struct pci_bus *bus, unsigned int fn, + int config, int size, u32 value) +{ + struct faraday_pci *p = bus->sysdata; + + dev_dbg(&bus->dev, + "[write] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n", + PCI_SLOT(fn), PCI_FUNC(fn), config, size, value); + + return faraday_raw_pci_write_config(p, bus->number, fn, config, size, + value); +} + +static struct pci_ops faraday_pci_ops = { + .read = faraday_pci_read_config, + .write = faraday_pci_write_config, +}; + +static void faraday_pci_ack_irq(struct irq_data *d) +{ + struct faraday_pci *p = irq_data_get_irq_chip_data(d); + unsigned int reg; + + faraday_raw_pci_read_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, ®); + reg &= ~(0xF << PCI_CTRL2_INTSTS_SHIFT); + reg |= BIT(irqd_to_hwirq(d) + PCI_CTRL2_INTSTS_SHIFT); + faraday_raw_pci_write_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, reg); +} + +static void faraday_pci_mask_irq(struct irq_data *d) +{ + struct faraday_pci *p = irq_data_get_irq_chip_data(d); + unsigned int reg; + + faraday_raw_pci_read_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, ®); + reg &= ~((0xF << PCI_CTRL2_INTSTS_SHIFT) + | BIT(irqd_to_hwirq(d) + PCI_CTRL2_INTMASK_SHIFT)); + faraday_raw_pci_write_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, reg); +} + +static void faraday_pci_unmask_irq(struct irq_data *d) +{ + struct faraday_pci *p = irq_data_get_irq_chip_data(d); + unsigned int reg; + + faraday_raw_pci_read_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, ®); + reg &= ~(0xF << PCI_CTRL2_INTSTS_SHIFT); + reg |= BIT(irqd_to_hwirq(d) + PCI_CTRL2_INTMASK_SHIFT); + faraday_raw_pci_write_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, reg); +} + +static void faraday_pci_irq_handler(struct irq_desc *desc) +{ + struct faraday_pci *p = irq_desc_get_handler_data(desc); + struct irq_chip *irqchip = irq_desc_get_chip(desc); + unsigned int irq_stat, reg, i; + + faraday_raw_pci_read_config(p, 0, 0, FARADAY_PCI_CTRL2, 4, ®); + irq_stat = reg >> PCI_CTRL2_INTSTS_SHIFT; + + chained_irq_enter(irqchip, desc); + + for (i = 0; i < 4; i++) { + if ((irq_stat & BIT(i)) == 0) + continue; + generic_handle_domain_irq(p->irqdomain, i); + } + + chained_irq_exit(irqchip, desc); +} + +static struct irq_chip faraday_pci_irq_chip = { + .name = "PCI", + .irq_ack = faraday_pci_ack_irq, + .irq_mask = faraday_pci_mask_irq, + .irq_unmask = faraday_pci_unmask_irq, +}; + +static int faraday_pci_irq_map(struct irq_domain *domain, unsigned int irq, + irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(irq, &faraday_pci_irq_chip, handle_level_irq); + irq_set_chip_data(irq, domain->host_data); + + return 0; +} + +static const struct irq_domain_ops faraday_pci_irqdomain_ops = { + .map = faraday_pci_irq_map, +}; + +static int faraday_pci_setup_cascaded_irq(struct faraday_pci *p) +{ + struct device_node *intc = of_get_next_child(p->dev->of_node, NULL); + int irq; + int i; + + if (!intc) { + dev_err(p->dev, "missing child interrupt-controller node\n"); + return -EINVAL; + } + + /* All PCI IRQs cascade off this one */ + irq = of_irq_get(intc, 0); + if (irq <= 0) { + dev_err(p->dev, "failed to get parent IRQ\n"); + of_node_put(intc); + return irq ?: -EINVAL; + } + + p->irqdomain = irq_domain_add_linear(intc, PCI_NUM_INTX, + &faraday_pci_irqdomain_ops, p); + of_node_put(intc); + if (!p->irqdomain) { + dev_err(p->dev, "failed to create Gemini PCI IRQ domain\n"); + return -EINVAL; + } + + irq_set_chained_handler_and_data(irq, faraday_pci_irq_handler, p); + + for (i = 0; i < 4; i++) + irq_create_mapping(p->irqdomain, i); + + return 0; +} + +static int faraday_pci_parse_map_dma_ranges(struct faraday_pci *p) +{ + struct device *dev = p->dev; + struct pci_host_bridge *bridge = pci_host_bridge_from_priv(p); + struct resource_entry *entry; + u32 confreg[3] = { + FARADAY_PCI_MEM1_BASE_SIZE, + FARADAY_PCI_MEM2_BASE_SIZE, + FARADAY_PCI_MEM3_BASE_SIZE, + }; + int i = 0; + u32 val; + + resource_list_for_each_entry(entry, &bridge->dma_ranges) { + u64 pci_addr = entry->res->start - entry->offset; + u64 end = entry->res->end - entry->offset; + int ret; + + ret = faraday_res_to_memcfg(pci_addr, + resource_size(entry->res), &val); + if (ret) { + dev_err(dev, + "DMA range %d: illegal MEM resource size\n", i); + return -EINVAL; + } + + dev_info(dev, "DMA MEM%d BASE: 0x%016llx -> 0x%016llx config %08x\n", + i + 1, pci_addr, end, val); + if (i <= 2) { + faraday_raw_pci_write_config(p, 0, 0, confreg[i], + 4, val); + } else { + dev_err(dev, "ignore extraneous dma-range %d\n", i); + break; + } + + i++; + } + + return 0; +} + +static int faraday_pci_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct faraday_pci_variant *variant = + of_device_get_match_data(dev); + struct resource_entry *win; + struct faraday_pci *p; + struct resource *io; + struct pci_host_bridge *host; + struct clk *clk; + unsigned char max_bus_speed = PCI_SPEED_33MHz; + unsigned char cur_bus_speed = PCI_SPEED_33MHz; + int ret; + u32 val; + + host = devm_pci_alloc_host_bridge(dev, sizeof(*p)); + if (!host) + return -ENOMEM; + + host->ops = &faraday_pci_ops; + p = pci_host_bridge_priv(host); + host->sysdata = p; + p->dev = dev; + + /* Retrieve and enable optional clocks */ + clk = devm_clk_get_enabled(dev, "PCLK"); + if (IS_ERR(clk)) + return PTR_ERR(clk); + p->bus_clk = devm_clk_get_enabled(dev, "PCICLK"); + if (IS_ERR(p->bus_clk)) + return PTR_ERR(p->bus_clk); + + p->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(p->base)) + return PTR_ERR(p->base); + + win = resource_list_first_type(&host->windows, IORESOURCE_IO); + if (win) { + io = win->res; + if (!faraday_res_to_memcfg(io->start - win->offset, + resource_size(io), &val)) { + /* setup I/O space size */ + writel(val, p->base + FTPCI_IOSIZE); + } else { + dev_err(dev, "illegal IO mem size\n"); + return -EINVAL; + } + } + + /* Setup hostbridge */ + val = readl(p->base + FTPCI_CTRL); + val |= PCI_COMMAND_IO; + val |= PCI_COMMAND_MEMORY; + val |= PCI_COMMAND_MASTER; + writel(val, p->base + FTPCI_CTRL); + /* Mask and clear all interrupts */ + faraday_raw_pci_write_config(p, 0, 0, FARADAY_PCI_CTRL2 + 2, 2, 0xF000); + if (variant->cascaded_irq) { + ret = faraday_pci_setup_cascaded_irq(p); + if (ret) { + dev_err(dev, "failed to setup cascaded IRQ\n"); + return ret; + } + } + + /* Check bus clock if we can gear up to 66 MHz */ + if (!IS_ERR(p->bus_clk)) { + unsigned long rate; + u32 val; + + faraday_raw_pci_read_config(p, 0, 0, + FARADAY_PCI_STATUS_CMD, 4, &val); + rate = clk_get_rate(p->bus_clk); + + if ((rate == 33000000) && (val & PCI_STATUS_66MHZ_CAPABLE)) { + dev_info(dev, "33MHz bus is 66MHz capable\n"); + max_bus_speed = PCI_SPEED_66MHz; + ret = clk_set_rate(p->bus_clk, 66000000); + if (ret) + dev_err(dev, "failed to set bus clock\n"); + } else { + dev_info(dev, "33MHz only bus\n"); + max_bus_speed = PCI_SPEED_33MHz; + } + + /* Bumping the clock may fail so read back the rate */ + rate = clk_get_rate(p->bus_clk); + if (rate == 33000000) + cur_bus_speed = PCI_SPEED_33MHz; + if (rate == 66000000) + cur_bus_speed = PCI_SPEED_66MHz; + } + + ret = faraday_pci_parse_map_dma_ranges(p); + if (ret) + return ret; + + ret = pci_scan_root_bus_bridge(host); + if (ret) { + dev_err(dev, "failed to scan host: %d\n", ret); + return ret; + } + p->bus = host->bus; + p->bus->max_bus_speed = max_bus_speed; + p->bus->cur_bus_speed = cur_bus_speed; + + pci_bus_assign_resources(p->bus); + pci_bus_add_devices(p->bus); + + return 0; +} + +/* + * We encode bridge variants here, we have at least two so it doesn't + * hurt to have infrastructure to encompass future variants as well. + */ +static const struct faraday_pci_variant faraday_regular = { + .cascaded_irq = true, +}; + +static const struct faraday_pci_variant faraday_dual = { + .cascaded_irq = false, +}; + +static const struct of_device_id faraday_pci_of_match[] = { + { + .compatible = "faraday,ftpci100", + .data = &faraday_regular, + }, + { + .compatible = "faraday,ftpci100-dual", + .data = &faraday_dual, + }, + {}, +}; + +static struct platform_driver faraday_pci_driver = { + .driver = { + .name = "ftpci100", + .of_match_table = of_match_ptr(faraday_pci_of_match), + .suppress_bind_attrs = true, + }, + .probe = faraday_pci_probe, +}; +builtin_platform_driver(faraday_pci_driver); |