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Release 4.16 drivers/pci/host/pci-ftpci100.c

Directory: drivers/pci/host
// 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>

/*
 * Special configuration registers directly in the first few words
 * in I/O space.
 */

#define PCI_IOSIZE	0x00

#define PCI_PROT	0x04 
/* AHB protection */

#define PCI_CTRL	0x08 
/* PCI control signal */

#define PCI_SOFTRST	0x10 
/* Soft reset counter and response error enable */

#define PCI_CONFIG	0x28 
/* PCI configuration command register */

#define PCI_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

/* Defines for PCI configuration command register */

#define PCI_CONF_ENABLE		BIT(31)

#define PCI_CONF_WHERE(r)	((r) & 0xFC)

#define PCI_CONF_BUS(b)		(((b) & 0xFF) << 16)

#define PCI_CONF_DEVICE(d)	(((d) & 0x1F) << 11)

#define PCI_CONF_FUNCTION(f)	(((f) & 0x07) << 8)

/**
 * 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; }

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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_CONF_BUS(bus_number) | PCI_CONF_DEVICE(PCI_SLOT(fn)) | PCI_CONF_FUNCTION(PCI_FUNC(fn)) | PCI_CONF_WHERE(config) | PCI_CONF_ENABLE, p->base + PCI_CONFIG); *value = readl(p->base + PCI_DATA); if (size == 1) *value = (*value >> (8 * (config & 3))) & 0xFF; else if (size == 2) *value = (*value >> (8 * (config & 3))) & 0xFFFF; return PCIBIOS_SUCCESSFUL; }

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Linus Walleij12694.74%150.00%
Lorenzo Pieralisi75.26%150.00%
Total133100.00%2100.00%


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); }

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Linus Walleij6075.95%150.00%
Lorenzo Pieralisi1924.05%150.00%
Total79100.00%2100.00%


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_CONF_BUS(bus_number) | PCI_CONF_DEVICE(PCI_SLOT(fn)) | PCI_CONF_FUNCTION(PCI_FUNC(fn)) | PCI_CONF_WHERE(config) | PCI_CONF_ENABLE, p->base + PCI_CONFIG); switch (size) { case 4: writel(value, p->base + PCI_DATA); break; case 2: writew(value, p->base + PCI_DATA + (config & 3)); break; case 1: writeb(value, p->base + PCI_DATA + (config & 3)); break; default: ret = PCIBIOS_BAD_REGISTER_NUMBER; } return ret; }

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Linus Walleij10474.29%150.00%
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Total140100.00%2100.00%


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); }

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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); 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); }

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Linus Walleij7192.21%150.00%
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Total77100.00%2100.00%


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); 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); }

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Linus Walleij7192.21%150.00%
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Total77100.00%2100.00%


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); 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); }

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Linus Walleij7192.21%150.00%
Lorenzo Pieralisi67.79%150.00%
Total77100.00%2100.00%


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, &reg); 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_irq(irq_find_mapping(p->irqdomain, i)); } chained_irq_exit(irqchip, desc); }

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Linus Walleij11397.41%150.00%
Lorenzo Pieralisi32.59%150.00%
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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; }

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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"); return irq ?: -EINVAL; } p->irqdomain = irq_domain_add_linear(intc, PCI_NUM_INTX, &faraday_pci_irqdomain_ops, p); 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; }

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Paul Burton10.63%133.33%
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static int faraday_pci_parse_map_dma_ranges(struct faraday_pci *p, struct device_node *np) { struct of_pci_range range; struct of_pci_range_parser parser; struct device *dev = p->dev; u32 confreg[3] = { FARADAY_PCI_MEM1_BASE_SIZE, FARADAY_PCI_MEM2_BASE_SIZE, FARADAY_PCI_MEM3_BASE_SIZE, }; int i = 0; u32 val; if (of_pci_dma_range_parser_init(&parser, np)) { dev_err(dev, "missing dma-ranges property\n"); return -EINVAL; } /* * Get the dma-ranges from the device tree */ for_each_of_pci_range(&parser, &range) { u64 end = range.pci_addr + range.size - 1; int ret; ret = faraday_res_to_memcfg(range.pci_addr, range.size, &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, range.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; }

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Marc Gonzalez10.50%133.33%
Total202100.00%3100.00%


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 *regs; resource_size_t io_base; struct resource_entry *win; struct faraday_pci *p; struct resource *mem; 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; LIST_HEAD(res); host = devm_pci_alloc_host_bridge(dev, sizeof(*p)); if (!host) return -ENOMEM; host->dev.parent = dev; host->ops = &faraday_pci_ops; host->busnr = 0; host->msi = NULL; host->map_irq = of_irq_parse_and_map_pci; host->swizzle_irq = pci_common_swizzle; p = pci_host_bridge_priv(host); host->sysdata = p; p->dev = dev; /* Retrieve and enable optional clocks */ clk = devm_clk_get(dev, "PCLK"); if (IS_ERR(clk)) return PTR_ERR(clk); ret = clk_prepare_enable(clk); if (ret) { dev_err(dev, "could not prepare PCLK\n"); return ret; } p->bus_clk = devm_clk_get(dev, "PCICLK"); if (IS_ERR(p->bus_clk)) return PTR_ERR(p->bus_clk); ret = clk_prepare_enable(p->bus_clk); if (ret) { dev_err(dev, "could not prepare PCICLK\n"); return ret; } regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); p->base = devm_ioremap_resource(dev, regs); if (IS_ERR(p->base)) return PTR_ERR(p->base); ret = of_pci_get_host_bridge_resources(dev->of_node, 0, 0xff, &res, &io_base); if (ret) return ret; ret = devm_request_pci_bus_resources(dev, &res); if (ret) return ret; /* Get the I/O and memory ranges from DT */ resource_list_for_each_entry(win, &res) { switch (resource_type(win->res)) { case IORESOURCE_IO: io = win->res; io->name = "Gemini PCI I/O"; if (!faraday_res_to_memcfg(io->start - win->offset, resource_size(io), &val)) { /* setup I/O space size */ writel(val, p->base + PCI_IOSIZE); } else { dev_err(dev, "illegal IO mem size\n"); return -EINVAL; } ret = pci_remap_iospace(io, io_base); if (ret) { dev_warn(dev, "error %d: failed to map resource %pR\n", ret, io); continue; } break; case IORESOURCE_MEM: mem = win->res; mem->name = "Gemini PCI MEM"; break; case IORESOURCE_BUS: break; default: break; } } /* Setup hostbridge */ val = readl(p->base + PCI_CTRL); val |= PCI_COMMAND_IO; val |= PCI_COMMAND_MEMORY; val |= PCI_COMMAND_MASTER; writel(val, p->base + PCI_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, dev->of_node); if (ret) return ret; list_splice_init(&res, &host->windows); 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); pci_free_resource_list(&res); return 0; }

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Linus Walleij74792.00%228.57%
Lorenzo Pieralisi627.64%457.14%
Wei Yongjun30.37%114.29%
Total812100.00%7100.00%

/* * We encode bridge variants here, we have at least two so it doesn't * hurt to have infrastructure to encompass future variants as well. */ const struct faraday_pci_variant faraday_regular = { .cascaded_irq = true, }; 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);

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Linus Walleij242090.94%216.67%
Lorenzo Pieralisi2258.46%433.33%
Brian Norris50.19%18.33%
Sergei Shtylyov50.19%18.33%
Wei Yongjun30.11%18.33%
Marc Gonzalez10.04%18.33%
Paul Burton10.04%18.33%
Greg Kroah-Hartman10.04%18.33%
Total2661100.00%12100.00%
Directory: drivers/pci/host
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