linux-stable/arch/mips/pci/pci-legacy.c
Huacai Chen 92db94fa51 MIPS/PCI: Call pcie_bus_configure_settings() to set MPS/MRRS
[ Upstream commit 2794f688b2 ]

Call pcie_bus_configure_settings() on MIPS, like for other platforms.
The function pcie_bus_configure_settings() makes sure the MPS (Max
Payload Size) across the bus is uniform and provides the ability to
tune the MRSS (Max Read Request Size) and MPS (Max Payload Size) to
higher performance values. Some devices will not operate properly if
these aren't set correctly because the firmware doesn't always do it.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20649/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: Huacai Chen <chenhuacai@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:19:10 +01:00

313 lines
7.6 KiB
C

/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* Copyright (C) 2003, 04, 11 Ralf Baechle (ralf@linux-mips.org)
* Copyright (C) 2011 Wind River Systems,
* written by Ralf Baechle (ralf@linux-mips.org)
*/
#include <linux/bug.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/of_address.h>
#include <asm/cpu-info.h>
/*
* If PCI_PROBE_ONLY in pci_flags is set, we don't change any PCI resource
* assignments.
*/
/*
* The PCI controller list.
*/
static LIST_HEAD(controllers);
static int pci_initialized;
/*
* We need to avoid collisions with `mirrored' VGA ports
* and other strange ISA hardware, so we always want the
* addresses to be allocated in the 0x000-0x0ff region
* modulo 0x400.
*
* Why? Because some silly external IO cards only decode
* the low 10 bits of the IO address. The 0x00-0xff region
* is reserved for motherboard devices that decode all 16
* bits, so it's ok to allocate at, say, 0x2800-0x28ff,
* but we want to try to avoid allocating at 0x2900-0x2bff
* which might have be mirrored at 0x0100-0x03ff..
*/
resource_size_t
pcibios_align_resource(void *data, const struct resource *res,
resource_size_t size, resource_size_t align)
{
struct pci_dev *dev = data;
struct pci_controller *hose = dev->sysdata;
resource_size_t start = res->start;
if (res->flags & IORESOURCE_IO) {
/* Make sure we start at our min on all hoses */
if (start < PCIBIOS_MIN_IO + hose->io_resource->start)
start = PCIBIOS_MIN_IO + hose->io_resource->start;
/*
* Put everything into 0x00-0xff region modulo 0x400
*/
if (start & 0x300)
start = (start + 0x3ff) & ~0x3ff;
} else if (res->flags & IORESOURCE_MEM) {
/* Make sure we start at our min on all hoses */
if (start < PCIBIOS_MIN_MEM + hose->mem_resource->start)
start = PCIBIOS_MIN_MEM + hose->mem_resource->start;
}
return start;
}
static void pcibios_scanbus(struct pci_controller *hose)
{
static int next_busno;
static int need_domain_info;
LIST_HEAD(resources);
struct pci_bus *bus;
struct pci_host_bridge *bridge;
int ret;
bridge = pci_alloc_host_bridge(0);
if (!bridge)
return;
if (hose->get_busno && pci_has_flag(PCI_PROBE_ONLY))
next_busno = (*hose->get_busno)();
pci_add_resource_offset(&resources,
hose->mem_resource, hose->mem_offset);
pci_add_resource_offset(&resources,
hose->io_resource, hose->io_offset);
pci_add_resource(&resources, hose->busn_resource);
list_splice_init(&resources, &bridge->windows);
bridge->dev.parent = NULL;
bridge->sysdata = hose;
bridge->busnr = next_busno;
bridge->ops = hose->pci_ops;
bridge->swizzle_irq = pci_common_swizzle;
bridge->map_irq = pcibios_map_irq;
ret = pci_scan_root_bus_bridge(bridge);
if (ret) {
pci_free_host_bridge(bridge);
return;
}
hose->bus = bus = bridge->bus;
need_domain_info = need_domain_info || pci_domain_nr(bus);
set_pci_need_domain_info(hose, need_domain_info);
next_busno = bus->busn_res.end + 1;
/* Don't allow 8-bit bus number overflow inside the hose -
reserve some space for bridges. */
if (next_busno > 224) {
next_busno = 0;
need_domain_info = 1;
}
/*
* We insert PCI resources into the iomem_resource and
* ioport_resource trees in either pci_bus_claim_resources()
* or pci_bus_assign_resources().
*/
if (pci_has_flag(PCI_PROBE_ONLY)) {
pci_bus_claim_resources(bus);
} else {
struct pci_bus *child;
pci_bus_size_bridges(bus);
pci_bus_assign_resources(bus);
list_for_each_entry(child, &bus->children, node)
pcie_bus_configure_settings(child);
}
pci_bus_add_devices(bus);
}
#ifdef CONFIG_OF
void pci_load_of_ranges(struct pci_controller *hose, struct device_node *node)
{
struct of_pci_range range;
struct of_pci_range_parser parser;
pr_info("PCI host bridge %pOF ranges:\n", node);
hose->of_node = node;
if (of_pci_range_parser_init(&parser, node))
return;
for_each_of_pci_range(&parser, &range) {
struct resource *res = NULL;
switch (range.flags & IORESOURCE_TYPE_BITS) {
case IORESOURCE_IO:
pr_info(" IO 0x%016llx..0x%016llx\n",
range.cpu_addr,
range.cpu_addr + range.size - 1);
hose->io_map_base =
(unsigned long)ioremap(range.cpu_addr,
range.size);
res = hose->io_resource;
break;
case IORESOURCE_MEM:
pr_info(" MEM 0x%016llx..0x%016llx\n",
range.cpu_addr,
range.cpu_addr + range.size - 1);
res = hose->mem_resource;
break;
}
if (res != NULL)
of_pci_range_to_resource(&range, node, res);
}
}
struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus)
{
struct pci_controller *hose = bus->sysdata;
return of_node_get(hose->of_node);
}
#endif
static DEFINE_MUTEX(pci_scan_mutex);
void register_pci_controller(struct pci_controller *hose)
{
struct resource *parent;
parent = hose->mem_resource->parent;
if (!parent)
parent = &iomem_resource;
if (request_resource(parent, hose->mem_resource) < 0)
goto out;
parent = hose->io_resource->parent;
if (!parent)
parent = &ioport_resource;
if (request_resource(parent, hose->io_resource) < 0) {
release_resource(hose->mem_resource);
goto out;
}
INIT_LIST_HEAD(&hose->list);
list_add_tail(&hose->list, &controllers);
/*
* Do not panic here but later - this might happen before console init.
*/
if (!hose->io_map_base) {
printk(KERN_WARNING
"registering PCI controller with io_map_base unset\n");
}
/*
* Scan the bus if it is register after the PCI subsystem
* initialization.
*/
if (pci_initialized) {
mutex_lock(&pci_scan_mutex);
pcibios_scanbus(hose);
mutex_unlock(&pci_scan_mutex);
}
return;
out:
printk(KERN_WARNING
"Skipping PCI bus scan due to resource conflict\n");
}
static int __init pcibios_init(void)
{
struct pci_controller *hose;
/* Scan all of the recorded PCI controllers. */
list_for_each_entry(hose, &controllers, list)
pcibios_scanbus(hose);
pci_initialized = 1;
return 0;
}
subsys_initcall(pcibios_init);
static int pcibios_enable_resources(struct pci_dev *dev, int mask)
{
u16 cmd, old_cmd;
int idx;
struct resource *r;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
old_cmd = cmd;
for (idx=0; idx < PCI_NUM_RESOURCES; idx++) {
/* Only set up the requested stuff */
if (!(mask & (1<<idx)))
continue;
r = &dev->resource[idx];
if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
continue;
if ((idx == PCI_ROM_RESOURCE) &&
(!(r->flags & IORESOURCE_ROM_ENABLE)))
continue;
if (!r->start && r->end) {
pci_err(dev,
"can't enable device: resource collisions\n");
return -EINVAL;
}
if (r->flags & IORESOURCE_IO)
cmd |= PCI_COMMAND_IO;
if (r->flags & IORESOURCE_MEM)
cmd |= PCI_COMMAND_MEMORY;
}
if (cmd != old_cmd) {
pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
return 0;
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
int err;
if ((err = pcibios_enable_resources(dev, mask)) < 0)
return err;
return pcibios_plat_dev_init(dev);
}
void pcibios_fixup_bus(struct pci_bus *bus)
{
struct pci_dev *dev = bus->self;
if (pci_has_flag(PCI_PROBE_ONLY) && dev &&
(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
pci_read_bridge_bases(bus);
}
}
char * (*pcibios_plat_setup)(char *str) __initdata;
char *__init pcibios_setup(char *str)
{
if (pcibios_plat_setup)
return pcibios_plat_setup(str);
return str;
}