linux/arch/xtensa/lib/pci-auto.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

317 lines
8.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* arch/xtensa/lib/pci-auto.c
*
* PCI autoconfiguration library
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*
* Chris Zankel <zankel@tensilica.com, cez@zankel.net>
*
* Based on work from Matt Porter <mporter@mvista.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <asm/pci-bridge.h>
/*
*
* Setting up a PCI
*
* pci_ctrl->first_busno = <first bus number (0)>
* pci_ctrl->last_busno = <last bus number (0xff)>
* pci_ctrl->ops = <PCI config operations>
* pci_ctrl->map_irq = <function to return the interrupt number for a device>
*
* pci_ctrl->io_space.start = <IO space start address (PCI view)>
* pci_ctrl->io_space.end = <IO space end address (PCI view)>
* pci_ctrl->io_space.base = <IO space offset: address 0 from CPU space>
* pci_ctrl->mem_space.start = <MEM space start address (PCI view)>
* pci_ctrl->mem_space.end = <MEM space end address (PCI view)>
* pci_ctrl->mem_space.base = <MEM space offset: address 0 from CPU space>
*
* pcibios_init_resource(&pci_ctrl->io_resource, <IO space start>,
* <IO space end>, IORESOURCE_IO, "PCI host bridge");
* pcibios_init_resource(&pci_ctrl->mem_resources[0], <MEM space start>,
* <MEM space end>, IORESOURCE_MEM, "PCI host bridge");
*
* pci_ctrl->last_busno = pciauto_bus_scan(pci_ctrl,pci_ctrl->first_busno);
*
* int __init pciauto_bus_scan(struct pci_controller *pci_ctrl, int current_bus)
*
*/
static int pciauto_upper_iospc;
static int pciauto_upper_memspc;
static struct pci_dev pciauto_dev;
static struct pci_bus pciauto_bus;
/*
* Helper functions
*/
/* Initialize the bars of a PCI device. */
static void __init
pciauto_setup_bars(struct pci_dev *dev, int bar_limit)
{
int bar_size;
int bar, bar_nr;
int *upper_limit;
int found_mem64 = 0;
for (bar = PCI_BASE_ADDRESS_0, bar_nr = 0;
bar <= bar_limit;
bar+=4, bar_nr++)
{
/* Tickle the BAR and get the size */
pci_write_config_dword(dev, bar, 0xffffffff);
pci_read_config_dword(dev, bar, &bar_size);
/* If BAR is not implemented go to the next BAR */
if (!bar_size)
continue;
/* Check the BAR type and set our address mask */
if (bar_size & PCI_BASE_ADDRESS_SPACE_IO)
{
bar_size &= PCI_BASE_ADDRESS_IO_MASK;
upper_limit = &pciauto_upper_iospc;
pr_debug("PCI Autoconfig: BAR %d, I/O, ", bar_nr);
}
else
{
if ((bar_size & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
PCI_BASE_ADDRESS_MEM_TYPE_64)
found_mem64 = 1;
bar_size &= PCI_BASE_ADDRESS_MEM_MASK;
upper_limit = &pciauto_upper_memspc;
pr_debug("PCI Autoconfig: BAR %d, Mem, ", bar_nr);
}
/* Allocate a base address (bar_size is negative!) */
*upper_limit = (*upper_limit + bar_size) & bar_size;
/* Write it out and update our limit */
pci_write_config_dword(dev, bar, *upper_limit);
/*
* If we are a 64-bit decoder then increment to the
* upper 32 bits of the bar and force it to locate
* in the lower 4GB of memory.
*/
if (found_mem64)
pci_write_config_dword(dev, (bar+=4), 0x00000000);
pr_debug("size=0x%x, address=0x%x\n",
~bar_size + 1, *upper_limit);
}
}
/* Initialize the interrupt number. */
static void __init
pciauto_setup_irq(struct pci_controller* pci_ctrl,struct pci_dev *dev,int devfn)
{
u8 pin;
int irq = 0;
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
/* Fix illegal pin numbers. */
if (pin == 0 || pin > 4)
pin = 1;
if (pci_ctrl->map_irq)
irq = pci_ctrl->map_irq(dev, PCI_SLOT(devfn), pin);
if (irq == -1)
irq = 0;
pr_debug("PCI Autoconfig: Interrupt %d, pin %d\n", irq, pin);
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
}
static void __init
pciauto_prescan_setup_bridge(struct pci_dev *dev, int current_bus,
int sub_bus, int *iosave, int *memsave)
{
/* Configure bus number registers */
pci_write_config_byte(dev, PCI_PRIMARY_BUS, current_bus);
pci_write_config_byte(dev, PCI_SECONDARY_BUS, sub_bus + 1);
pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, 0xff);
/* Round memory allocator to 1MB boundary */
pciauto_upper_memspc &= ~(0x100000 - 1);
*memsave = pciauto_upper_memspc;
/* Round I/O allocator to 4KB boundary */
pciauto_upper_iospc &= ~(0x1000 - 1);
*iosave = pciauto_upper_iospc;
/* Set up memory and I/O filter limits, assume 32-bit I/O space */
pci_write_config_word(dev, PCI_MEMORY_LIMIT,
((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
pci_write_config_byte(dev, PCI_IO_LIMIT,
((pciauto_upper_iospc - 1) & 0x0000f000) >> 8);
pci_write_config_word(dev, PCI_IO_LIMIT_UPPER16,
((pciauto_upper_iospc - 1) & 0xffff0000) >> 16);
}
static void __init
pciauto_postscan_setup_bridge(struct pci_dev *dev, int current_bus, int sub_bus,
int *iosave, int *memsave)
{
int cmdstat;
/* Configure bus number registers */
pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, sub_bus);
/*
* Round memory allocator to 1MB boundary.
* If no space used, allocate minimum.
*/
pciauto_upper_memspc &= ~(0x100000 - 1);
if (*memsave == pciauto_upper_memspc)
pciauto_upper_memspc -= 0x00100000;
pci_write_config_word(dev, PCI_MEMORY_BASE, pciauto_upper_memspc >> 16);
/* Allocate 1MB for pre-fretch */
pci_write_config_word(dev, PCI_PREF_MEMORY_LIMIT,
((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
pciauto_upper_memspc -= 0x100000;
pci_write_config_word(dev, PCI_PREF_MEMORY_BASE,
pciauto_upper_memspc >> 16);
/* Round I/O allocator to 4KB boundary */
pciauto_upper_iospc &= ~(0x1000 - 1);
if (*iosave == pciauto_upper_iospc)
pciauto_upper_iospc -= 0x1000;
pci_write_config_byte(dev, PCI_IO_BASE,
(pciauto_upper_iospc & 0x0000f000) >> 8);
pci_write_config_word(dev, PCI_IO_BASE_UPPER16,
pciauto_upper_iospc >> 16);
/* Enable memory and I/O accesses, enable bus master */
pci_read_config_dword(dev, PCI_COMMAND, &cmdstat);
pci_write_config_dword(dev, PCI_COMMAND,
cmdstat |
PCI_COMMAND_IO |
PCI_COMMAND_MEMORY |
PCI_COMMAND_MASTER);
}
/*
* Scan the current PCI bus.
*/
int __init pciauto_bus_scan(struct pci_controller *pci_ctrl, int current_bus)
{
int sub_bus, pci_devfn, pci_class, cmdstat, found_multi=0;
unsigned short vid;
unsigned char header_type;
struct pci_dev *dev = &pciauto_dev;
pciauto_dev.bus = &pciauto_bus;
pciauto_dev.sysdata = pci_ctrl;
pciauto_bus.ops = pci_ctrl->ops;
/*
* Fetch our I/O and memory space upper boundaries used
* to allocated base addresses on this pci_controller.
*/
if (current_bus == pci_ctrl->first_busno)
{
pciauto_upper_iospc = pci_ctrl->io_resource.end + 1;
pciauto_upper_memspc = pci_ctrl->mem_resources[0].end + 1;
}
sub_bus = current_bus;
for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++)
{
/* Skip our host bridge */
if ((current_bus == pci_ctrl->first_busno) && (pci_devfn == 0))
continue;
if (PCI_FUNC(pci_devfn) && !found_multi)
continue;
pciauto_bus.number = current_bus;
pciauto_dev.devfn = pci_devfn;
/* If config space read fails from this device, move on */
if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type))
continue;
if (!PCI_FUNC(pci_devfn))
found_multi = header_type & 0x80;
pci_read_config_word(dev, PCI_VENDOR_ID, &vid);
if (vid == 0xffff || vid == 0x0000) {
found_multi = 0;
continue;
}
pci_read_config_dword(dev, PCI_CLASS_REVISION, &pci_class);
if ((pci_class >> 16) == PCI_CLASS_BRIDGE_PCI) {
int iosave, memsave;
pr_debug("PCI Autoconfig: Found P2P bridge, device %d\n",
PCI_SLOT(pci_devfn));
/* Allocate PCI I/O and/or memory space */
pciauto_setup_bars(dev, PCI_BASE_ADDRESS_1);
pciauto_prescan_setup_bridge(dev, current_bus, sub_bus,
&iosave, &memsave);
sub_bus = pciauto_bus_scan(pci_ctrl, sub_bus+1);
pciauto_postscan_setup_bridge(dev, current_bus, sub_bus,
&iosave, &memsave);
pciauto_bus.number = current_bus;
continue;
}
/*
* Found a peripheral, enable some standard
* settings
*/
pci_read_config_dword(dev, PCI_COMMAND, &cmdstat);
pci_write_config_dword(dev, PCI_COMMAND,
cmdstat |
PCI_COMMAND_IO |
PCI_COMMAND_MEMORY |
PCI_COMMAND_MASTER);
pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0x80);
/* Allocate PCI I/O and/or memory space */
pr_debug("PCI Autoconfig: Found Bus %d, Device %d, Function %d\n",
current_bus, PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn));
pciauto_setup_bars(dev, PCI_BASE_ADDRESS_5);
pciauto_setup_irq(pci_ctrl, dev, pci_devfn);
}
return sub_bus;
}