// SPDX-License-Identifier: GPL-2.0
/*
* Support for Faraday Technology FTPC100 PCI Controller
*
* Copyright (C) 2017 Linus Walleij <[email protected]>
*
* Based on the out-of-tree OpenWRT patch for Cortina Gemini:
* Copyright (C) 2009 Janos Laube <[email protected]>
* Copyright (C) 2009 Paulius Zaleckas <[email protected]>
* 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.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 = faraday_pci_of_match,
.suppress_bind_attrs = true,
},
.probe = faraday_pci_probe,
};
builtin_platform_driver(faraday_pci_driver);
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