// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/arm/kernel/bios32.c
*
* PCI bios-type initialisation for PCI machines
*
* Bits taken from various places.
*/
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/io.h>
#include <asm/mach-types.h>
#include <asm/mach/map.h>
#include <asm/mach/pci.h>
static int debug_pci;
/*
* We can't use pci_get_device() here since we are
* called from interrupt context.
*/
static void pcibios_bus_report_status(struct pci_bus *bus, u_int status_mask, int warn)
{
struct pci_dev *dev;
list_for_each_entry(dev, &bus->devices, bus_list) {
u16 status;
/*
* ignore host bridge - we handle
* that separately
*/
if (dev->bus->number == 0 && dev->devfn == 0)
continue;
pci_read_config_word(dev, PCI_STATUS, &status);
if (status == 0xffff)
continue;
if ((status & status_mask) == 0)
continue;
/* clear the status errors */
pci_write_config_word(dev, PCI_STATUS, status & status_mask);
if (warn)
printk("(%s: %04X) ", pci_name(dev), status);
}
list_for_each_entry(dev, &bus->devices, bus_list)
if (dev->subordinate)
pcibios_bus_report_status(dev->subordinate, status_mask, warn);
}
void pcibios_report_status(u_int status_mask, int warn)
{
struct pci_bus *bus;
list_for_each_entry(bus, &pci_root_buses, node)
pcibios_bus_report_status(bus, status_mask, warn);
}
/*
* We don't use this to fix the device, but initialisation of it.
* It's not the correct use for this, but it works.
* Note that the arbiter/ISA bridge appears to be buggy, specifically in
* the following area:
* 1. park on CPU
* 2. ISA bridge ping-pong
* 3. ISA bridge master handling of target RETRY
*
* Bug 3 is responsible for the sound DMA grinding to a halt. We now
* live with bug 2.
*/
static void pci_fixup_83c553(struct pci_dev *dev)
{
/*
* Set memory region to start at address 0, and enable IO
*/
pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, PCI_BASE_ADDRESS_SPACE_MEMORY);
pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_IO);
dev->resource[0].end -= dev->resource[0].start;
dev->resource[0].start = 0;
/*
* All memory requests from ISA to be channelled to PCI
*/
pci_write_config_byte(dev, 0x48, 0xff);
/*
* Enable ping-pong on bus master to ISA bridge transactions.
* This improves the sound DMA substantially. The fixed
* priority arbiter also helps (see below).
*/
pci_write_config_byte(dev, 0x42, 0x01);
/*
* Enable PCI retry
*/
pci_write_config_byte(dev, 0x40, 0x22);
/*
* We used to set the arbiter to "park on last master" (bit
* 1 set), but unfortunately the CyberPro does not park the
* bus. We must therefore park on CPU. Unfortunately, this
* may trigger yet another bug in the 553.
*/
pci_write_config_byte(dev, 0x83, 0x02);
/*
* Make the ISA DMA request lowest priority, and disable
* rotating priorities completely.
*/
pci_write_config_byte(dev, 0x80, 0x11);
pci_write_config_byte(dev, 0x81, 0x00);
/*
* Route INTA input to IRQ 11, and set IRQ11 to be level
* sensitive.
*/
pci_write_config_word(dev, 0x44, 0xb000);
outb(0x08, 0x4d1);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_83C553, pci_fixup_83c553);
static void pci_fixup_unassign(struct pci_dev *dev)
{
dev->resource[0].end -= dev->resource[0].start;
dev->resource[0].start = 0;
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND2, PCI_DEVICE_ID_WINBOND2_89C940F, pci_fixup_unassign);
/*
* Prevent the PCI layer from seeing the resources allocated to this device
* if it is the host bridge by marking it as such. These resources are of
* no consequence to the PCI layer (they are handled elsewhere).
*/
static void pci_fixup_dec21285(struct pci_dev *dev)
{
if (dev->devfn == 0) {
struct resource *r;
dev->class &= 0xff;
dev->class |= PCI_CLASS_BRIDGE_HOST << 8;
pci_dev_for_each_resource(dev, r) {
r->start = 0;
r->end = 0;
r->flags = 0;
}
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21285, pci_fixup_dec21285);
/*
* PCI IDE controllers use non-standard I/O port decoding, respect it.
*/
static void pci_fixup_ide_bases(struct pci_dev *dev)
{
struct resource *r;
if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE)
return;
pci_dev_for_each_resource(dev, r) {
if ((r->start & ~0x80) == 0x374) {
r->start |= 2;
r->end = r->start;
}
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_ide_bases);
/*
* Put the DEC21142 to sleep
*/
static void pci_fixup_dec21142(struct pci_dev *dev)
{
pci_write_config_dword(dev, 0x40, 0x80000000);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21142, pci_fixup_dec21142);
/*
* The CY82C693 needs some rather major fixups to ensure that it does
* the right thing. Idea from the Alpha people, with a few additions.
*
* We ensure that the IDE base registers are set to 1f0/3f4 for the
* primary bus, and 170/374 for the secondary bus. Also, hide them
* from the PCI subsystem view as well so we won't try to perform
* our own auto-configuration on them.
*
* In addition, we ensure that the PCI IDE interrupts are routed to
* IRQ 14 and IRQ 15 respectively.
*
* The above gets us to a point where the IDE on this device is
* functional. However, The CY82C693U _does not work_ in bus
* master mode without locking the PCI bus solid.
*/
static void pci_fixup_cy82c693(struct pci_dev *dev)
{
if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
u32 base0, base1;
if (dev->class & 0x80) { /* primary */
base0 = 0x1f0;
base1 = 0x3f4;
} else { /* secondary */
base0 = 0x170;
base1 = 0x374;
}
pci_write_config_dword(dev, PCI_BASE_ADDRESS_0,
base0 | PCI_BASE_ADDRESS_SPACE_IO);
pci_write_config_dword(dev, PCI_BASE_ADDRESS_1,
base1 | PCI_BASE_ADDRESS_SPACE_IO);
dev->resource[0].start = 0;
dev->resource[0].end = 0;
dev->resource[0].flags = 0;
dev->resource[1].start = 0;
dev->resource[1].end = 0;
dev->resource[1].flags = 0;
} else if (PCI_FUNC(dev->devfn) == 0) {
/*
* Setup IDE IRQ routing.
*/
pci_write_config_byte(dev, 0x4b, 14);
pci_write_config_byte(dev, 0x4c, 15);
/*
* Disable FREQACK handshake, enable USB.
*/
pci_write_config_byte(dev, 0x4d, 0x41);
/*
* Enable PCI retry, and PCI post-write buffer.
*/
pci_write_config_byte(dev, 0x44, 0x17);
/*
* Enable ISA master and DMA post write buffering.
*/
pci_write_config_byte(dev, 0x45, 0x03);
}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CONTAQ, PCI_DEVICE_ID_CONTAQ_82C693, pci_fixup_cy82c693);
/*
* If the bus contains any of these devices, then we must not turn on
* parity checking of any kind. Currently this is CyberPro 20x0 only.
*/
static inline int pdev_bad_for_parity(struct pci_dev *dev)
{
return ((dev->vendor == PCI_VENDOR_ID_INTERG &&
(dev->device == PCI_DEVICE_ID_INTERG_2000 ||
dev->device == PCI_DEVICE_ID_INTERG_2010)) ||
(dev->vendor == PCI_VENDOR_ID_ITE &&
dev->device == PCI_DEVICE_ID_ITE_8152));
}
/*
* pcibios_fixup_bus - Called after each bus is probed,
* but before its children are examined.
*/
void pcibios_fixup_bus(struct pci_bus *bus)
{
struct pci_dev *dev;
u16 features = PCI_COMMAND_SERR | PCI_COMMAND_PARITY | PCI_COMMAND_FAST_BACK;
/*
* Walk the devices on this bus, working out what we can
* and can't support.
*/
list_for_each_entry(dev, &bus->devices, bus_list) {
u16 status;
pci_read_config_word(dev, PCI_STATUS, &status);
/*
* If any device on this bus does not support fast back
* to back transfers, then the bus as a whole is not able
* to support them. Having fast back to back transfers
* on saves us one PCI cycle per transaction.
*/
if (!(status & PCI_STATUS_FAST_BACK))
features &= ~PCI_COMMAND_FAST_BACK;
if (pdev_bad_for_parity(dev))
features &= ~(PCI_COMMAND_SERR | PCI_COMMAND_PARITY);
switch (dev->class >> 8) {
case PCI_CLASS_BRIDGE_PCI:
pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &status);
status |= PCI_BRIDGE_CTL_PARITY|PCI_BRIDGE_CTL_MASTER_ABORT;
status &= ~(PCI_BRIDGE_CTL_BUS_RESET|PCI_BRIDGE_CTL_FAST_BACK);
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, status);
break;
case PCI_CLASS_BRIDGE_CARDBUS:
pci_read_config_word(dev, PCI_CB_BRIDGE_CONTROL, &status);
status |= PCI_CB_BRIDGE_CTL_PARITY|PCI_CB_BRIDGE_CTL_MASTER_ABORT;
pci_write_config_word(dev, PCI_CB_BRIDGE_CONTROL, status);
break;
}
}
/*
* Now walk the devices again, this time setting them up.
*/
list_for_each_entry(dev, &bus->devices, bus_list) {
u16 cmd;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
cmd |= features;
pci_write_config_word(dev, PCI_COMMAND, cmd);
pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
L1_CACHE_BYTES >> 2);
}
/*
* Propagate the flags to the PCI bridge.
*/
if (bus->self && bus->self->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
if (features & PCI_COMMAND_FAST_BACK)
bus->bridge_ctl |= PCI_BRIDGE_CTL_FAST_BACK;
if (features & PCI_COMMAND_PARITY)
bus->bridge_ctl |= PCI_BRIDGE_CTL_PARITY;
}
/*
* Report what we did for this bus
*/
pr_info("PCI: bus%d: Fast back to back transfers %sabled\n",
bus->number, (features & PCI_COMMAND_FAST_BACK) ? "en" : "dis");
}
EXPORT_SYMBOL(pcibios_fixup_bus);
/*
* Swizzle the device pin each time we cross a bridge. If a platform does
* not provide a swizzle function, we perform the standard PCI swizzling.
*
* The default swizzling walks up the bus tree one level at a time, applying
* the standard swizzle function at each step, stopping when it finds the PCI
* root bus. This will return the slot number of the bridge device on the
* root bus and the interrupt pin on that device which should correspond
* with the downstream device interrupt.
*
* Platforms may override this, in which case the slot and pin returned
* depend entirely on the platform code. However, please note that the
* PCI standard swizzle is implemented on plug-in cards and Cardbus based
* PCI extenders, so it can not be ignored.
*/
static u8 pcibios_swizzle(struct pci_dev *dev, u8 *pin)
{
struct pci_sys_data *sys = dev->sysdata;
int slot, oldpin = *pin;
if (sys->swizzle)
slot = sys->swizzle(dev, pin);
else
slot = pci_common_swizzle(dev, pin);
if (debug_pci)
printk("PCI: %s swizzling pin %d => pin %d slot %d\n",
pci_name(dev), oldpin, *pin, slot);
return slot;
}
/*
* Map a slot/pin to an IRQ.
*/
static int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
struct pci_sys_data *sys = dev->sysdata;
int irq = -1;
if (sys->map_irq)
irq = sys->map_irq(dev, slot, pin);
if (debug_pci)
printk("PCI: %s mapping slot %d pin %d => irq %d\n",
pci_name(dev), slot, pin, irq);
return irq;
}
static int pcibios_init_resource(int busnr, struct pci_sys_data *sys)
{
int ret;
struct resource_entry *window;
if (list_empty(&sys->resources)) {
pci_add_resource_offset(&sys->resources,
&iomem_resource, sys->mem_offset);
}
resource_list_for_each_entry(window, &sys->resources)
if (resource_type(window->res) == IORESOURCE_IO)
return 0;
sys->io_res.start = (busnr * SZ_64K) ? : pcibios_min_io;
sys->io_res.end = (busnr + 1) * SZ_64K - 1;
sys->io_res.flags = IORESOURCE_IO;
sys->io_res.name = sys->io_res_name;
sprintf(sys->io_res_name, "PCI%d I/O", busnr);
ret = request_resource(&ioport_resource, &sys->io_res);
if (ret) {
pr_err("PCI: unable to allocate I/O port region (%d)\n", ret);
return ret;
}
pci_add_resource_offset(&sys->resources, &sys->io_res,
sys->io_offset);
return 0;
}
static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
struct list_head *head)
{
struct pci_sys_data *sys = NULL;
int ret;
int nr, busnr;
for (nr = busnr = 0; nr < hw->nr_controllers; nr++) {
struct pci_host_bridge *bridge;
bridge = pci_alloc_host_bridge(sizeof(struct pci_sys_data));
if (WARN(!bridge, "PCI: unable to allocate bridge!"))
break;
sys = pci_host_bridge_priv(bridge);
sys->busnr = busnr;
sys->swizzle = hw->swizzle;
sys->map_irq = hw->map_irq;
INIT_LIST_HEAD(&sys->resources);
if (hw->private_data)
sys->private_data = hw->private_data[nr];
ret = hw->setup(nr, sys);
if (ret > 0) {
ret = pcibios_init_resource(nr, sys);
if (ret) {
pci_free_host_bridge(bridge);
break;
}
bridge->map_irq = pcibios_map_irq;
bridge->swizzle_irq = pcibios_swizzle;
if (hw->scan)
ret = hw->scan(nr, bridge);
else {
list_splice_init(&sys->resources,
&bridge->windows);
bridge->dev.parent = parent;
bridge->sysdata = sys;
bridge->busnr = sys->busnr;
bridge->ops = hw->ops;
ret = pci_scan_root_bus_bridge(bridge);
}
if (WARN(ret < 0, "PCI: unable to scan bus!")) {
pci_free_host_bridge(bridge);
break;
}
sys->bus = bridge->bus;
busnr = sys->bus->busn_res.end + 1;
list_add(&sys->node, head);
} else {
pci_free_host_bridge(bridge);
if (ret < 0)
break;
}
}
}
void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
{
struct pci_sys_data *sys;
LIST_HEAD(head);
pci_add_flags(PCI_REASSIGN_ALL_BUS);
if (hw->preinit)
hw->preinit();
pcibios_init_hw(parent, hw, &head);
if (hw->postinit)
hw->postinit();
list_for_each_entry(sys, &head, node) {
struct pci_bus *bus = sys->bus;
/*
* 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);
}
}
#ifndef CONFIG_PCI_HOST_ITE8152
void pcibios_set_master(struct pci_dev *dev)
{
/* No special bus mastering setup handling */
}
#endif
char * __init pcibios_setup(char *str)
{
if (!strcmp(str, "debug")) {
debug_pci = 1;
return NULL;
}
return str;
}
/*
* From arch/i386/kernel/pci-i386.c:
*
* 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 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;
resource_size_t start = res->start;
struct pci_host_bridge *host_bridge;
if (res->flags & IORESOURCE_IO && start & 0x300)
start = (start + 0x3ff) & ~0x3ff;
start = (start + align - 1) & ~(align - 1);
host_bridge = pci_find_host_bridge(dev->bus);
if (host_bridge->align_resource)
return host_bridge->align_resource(dev, res,
start, size, align);
return start;
}
void __init pci_map_io_early(unsigned long pfn)
{
struct map_desc pci_io_desc = {
.virtual = PCI_IO_VIRT_BASE,
.type = MT_DEVICE,
.length = SZ_64K,
};
pci_io_desc.pfn = pfn;
iotable_init(&pci_io_desc, 1);
}
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