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author | H. Peter Anvin <hpa@zytor.com> | 2008-03-26 16:25:35 -0700 |
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committer | H. Peter Anvin <hpa@zytor.com> | 2008-03-26 16:25:35 -0700 |
commit | 9eddd22a7b53b1d02fbae0d987df8af122924248 (patch) | |
tree | 882f5152880b0b1aa2d7a0619d30065acc69fb16 /gpxe/src/drivers/bus/pci.c | |
parent | bbb8f15936b851e6a0ef6f7bb2c95197bff35994 (diff) | |
download | syslinux-9eddd22a7b53b1d02fbae0d987df8af122924248.tar.gz |
Add gPXE into the source tree; build unified imagesyslinux-3.70-pre7
Diffstat (limited to 'gpxe/src/drivers/bus/pci.c')
-rw-r--r-- | gpxe/src/drivers/bus/pci.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/gpxe/src/drivers/bus/pci.c b/gpxe/src/drivers/bus/pci.c new file mode 100644 index 00000000..967441ac --- /dev/null +++ b/gpxe/src/drivers/bus/pci.c @@ -0,0 +1,343 @@ +/* + * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>. + * + * Based in part on pci.c from Etherboot 5.4, by Ken Yap and David + * Munro, in turn based on the Linux kernel's PCI implementation. + * + * 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 any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <stdint.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <gpxe/tables.h> +#include <gpxe/device.h> +#include <gpxe/pci.h> + +/** @file + * + * PCI bus + * + */ + +static struct pci_driver pci_drivers[0] + __table_start ( struct pci_driver, pci_drivers ); +static struct pci_driver pci_drivers_end[0] + __table_end ( struct pci_driver, pci_drivers ); + +static void pcibus_remove ( struct root_device *rootdev ); + +/** + * Read PCI BAR + * + * @v pci PCI device + * @v reg PCI register number + * @ret bar Base address register + * + * Reads the specified PCI base address register, including the flags + * portion. 64-bit BARs will be handled automatically. If the value + * of the 64-bit BAR exceeds the size of an unsigned long (i.e. if the + * high dword is non-zero on a 32-bit platform), then the value + * returned will be zero plus the flags for a 64-bit BAR. Unreachable + * 64-bit BARs are therefore returned as uninitialised 64-bit BARs. + */ +static unsigned long pci_bar ( struct pci_device *pci, unsigned int reg ) { + uint32_t low; + uint32_t high; + + pci_read_config_dword ( pci, reg, &low ); + if ( ( low & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK) ) + == (PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64) ){ + pci_read_config_dword ( pci, reg + 4, &high ); + if ( high ) { + if ( sizeof ( unsigned long ) > sizeof ( uint32_t ) ) { + return ( ( ( uint64_t ) high << 32 ) | low ); + } else { + DBG ( "Unhandled 64-bit BAR %08lx%08lx\n", + high, low ); + return PCI_BASE_ADDRESS_MEM_TYPE_64; + } + } + } + return low; +} + +/** + * Find the start of a PCI BAR + * + * @v pci PCI device + * @v reg PCI register number + * @ret start BAR start address + * + * Reads the specified PCI base address register, and returns the + * address portion of the BAR (i.e. without the flags). + * + * If the address exceeds the size of an unsigned long (i.e. if a + * 64-bit BAR has a non-zero high dword on a 32-bit machine), the + * return value will be zero. + */ +unsigned long pci_bar_start ( struct pci_device *pci, unsigned int reg ) { + unsigned long bar; + + bar = pci_bar ( pci, reg ); + if ( (bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_MEMORY ){ + return ( bar & PCI_BASE_ADDRESS_MEM_MASK ); + } else { + return ( bar & PCI_BASE_ADDRESS_IO_MASK ); + } +} + +/** + * Read membase and ioaddr for a PCI device + * + * @v pci PCI device + * + * This scans through all PCI BARs on the specified device. The first + * valid memory BAR is recorded as pci_device::membase, and the first + * valid IO BAR is recorded as pci_device::ioaddr. + * + * 64-bit BARs are handled automatically. On a 32-bit platform, if a + * 64-bit BAR has a non-zero high dword, it will be regarded as + * invalid. + */ +static void pci_read_bases ( struct pci_device *pci ) { + unsigned long bar; + int reg; + + for ( reg = PCI_BASE_ADDRESS_0; reg <= PCI_BASE_ADDRESS_5; reg += 4 ) { + bar = pci_bar ( pci, reg ); + if ( bar & PCI_BASE_ADDRESS_SPACE_IO ) { + if ( ! pci->ioaddr ) + pci->ioaddr = + ( bar & PCI_BASE_ADDRESS_IO_MASK ); + } else { + if ( ! pci->membase ) + pci->membase = + ( bar & PCI_BASE_ADDRESS_MEM_MASK ); + /* Skip next BAR if 64-bit */ + if ( bar & PCI_BASE_ADDRESS_MEM_TYPE_64 ) + reg += 4; + } + } +} + +/** + * Enable PCI device + * + * @v pci PCI device + * + * Set device to be a busmaster in case BIOS neglected to do so. Also + * adjust PCI latency timer to a reasonable value, 32. + */ +void adjust_pci_device ( struct pci_device *pci ) { + unsigned short new_command, pci_command; + unsigned char pci_latency; + + pci_read_config_word ( pci, PCI_COMMAND, &pci_command ); + new_command = pci_command | PCI_COMMAND_MASTER | PCI_COMMAND_IO; + if ( pci_command != new_command ) { + DBG ( "PCI BIOS has not enabled device %02x:%02x.%x! " + "Updating PCI command %04x->%04x\n", pci->bus, + PCI_SLOT ( pci->devfn ), PCI_FUNC ( pci->devfn ), + pci_command, new_command ); + pci_write_config_word ( pci, PCI_COMMAND, new_command ); + } + + pci_read_config_byte ( pci, PCI_LATENCY_TIMER, &pci_latency); + if ( pci_latency < 32 ) { + DBG ( "PCI device %02x:%02x.%x latency timer is unreasonably " + "low at %d. Setting to 32.\n", pci->bus, + PCI_SLOT ( pci->devfn ), PCI_FUNC ( pci->devfn ), + pci_latency ); + pci_write_config_byte ( pci, PCI_LATENCY_TIMER, 32); + } +} + +/** + * Probe a PCI device + * + * @v pci PCI device + * @ret rc Return status code + * + * Searches for a driver for the PCI device. If a driver is found, + * its probe() routine is called. + */ +static int pci_probe ( struct pci_device *pci ) { + struct pci_driver *driver; + struct pci_device_id *id; + unsigned int i; + int rc; + + DBG ( "Adding PCI device %02x:%02x.%x (%04x:%04x mem %lx io %lx " + "irq %d)\n", pci->bus, PCI_SLOT ( pci->devfn ), + PCI_FUNC ( pci->devfn ), pci->vendor, pci->device, + pci->membase, pci->ioaddr, pci->irq ); + + for ( driver = pci_drivers ; driver < pci_drivers_end ; driver++ ) { + for ( i = 0 ; i < driver->id_count ; i++ ) { + id = &driver->ids[i]; + if ( ( id->vendor != PCI_ANY_ID ) && + ( id->vendor != pci->vendor ) ) + continue; + if ( ( id->device != PCI_ANY_ID ) && + ( id->device != pci->device ) ) + continue; + pci->driver = driver; + pci->driver_name = id->name; + DBG ( "...using driver %s\n", pci->driver_name ); + if ( ( rc = driver->probe ( pci, id ) ) != 0 ) { + DBG ( "......probe failed\n" ); + continue; + } + return 0; + } + } + + DBG ( "...no driver found\n" ); + return -ENOTTY; +} + +/** + * Remove a PCI device + * + * @v pci PCI device + */ +static void pci_remove ( struct pci_device *pci ) { + pci->driver->remove ( pci ); + DBG ( "Removed PCI device %02x:%02x.%x\n", pci->bus, + PCI_SLOT ( pci->devfn ), PCI_FUNC ( pci->devfn ) ); +} + +/** + * Probe PCI root bus + * + * @v rootdev PCI bus root device + * + * Scans the PCI bus for devices and registers all devices it can + * find. + */ +static int pcibus_probe ( struct root_device *rootdev ) { + struct pci_device *pci = NULL; + unsigned int max_bus; + unsigned int bus; + unsigned int devfn; + uint8_t hdrtype = 0; + uint32_t tmp; + int rc; + + max_bus = pci_max_bus(); + for ( bus = 0 ; bus <= max_bus ; bus++ ) { + for ( devfn = 0 ; devfn <= 0xff ; devfn++ ) { + + /* Allocate struct pci_device */ + if ( ! pci ) + pci = malloc ( sizeof ( *pci ) ); + if ( ! pci ) { + rc = -ENOMEM; + goto err; + } + memset ( pci, 0, sizeof ( *pci ) ); + pci->bus = bus; + pci->devfn = devfn; + + /* Skip all but the first function on + * non-multifunction cards + */ + if ( PCI_FUNC ( devfn ) == 0 ) { + pci_read_config_byte ( pci, PCI_HEADER_TYPE, + &hdrtype ); + } else if ( ! ( hdrtype & 0x80 ) ) { + continue; + } + + /* Check for physical device presence */ + pci_read_config_dword ( pci, PCI_VENDOR_ID, &tmp ); + if ( ( tmp == 0xffffffff ) || ( tmp == 0 ) ) + continue; + + /* Populate struct pci_device */ + pci->vendor = ( tmp & 0xffff ); + pci->device = ( tmp >> 16 ); + pci_read_config_dword ( pci, PCI_REVISION, &tmp ); + pci->class = ( tmp >> 8 ); + pci_read_config_byte ( pci, PCI_INTERRUPT_LINE, + &pci->irq ); + pci_read_bases ( pci ); + + /* Add to device hierarchy */ + snprintf ( pci->dev.name, sizeof ( pci->dev.name ), + "PCI%02x:%02x.%x", bus, + PCI_SLOT ( devfn ), PCI_FUNC ( devfn ) ); + pci->dev.desc.bus_type = BUS_TYPE_PCI; + pci->dev.desc.location = PCI_BUSDEVFN (bus, devfn); + pci->dev.desc.vendor = pci->vendor; + pci->dev.desc.device = pci->device; + pci->dev.desc.class = pci->class; + pci->dev.desc.ioaddr = pci->ioaddr; + pci->dev.desc.irq = pci->irq; + pci->dev.parent = &rootdev->dev; + list_add ( &pci->dev.siblings, &rootdev->dev.children); + INIT_LIST_HEAD ( &pci->dev.children ); + + /* Look for a driver */ + if ( pci_probe ( pci ) == 0 ) { + /* pcidev registered, we can drop our ref */ + pci = NULL; + } else { + /* Not registered; re-use struct pci_device */ + list_del ( &pci->dev.siblings ); + } + } + } + + free ( pci ); + return 0; + + err: + free ( pci ); + pcibus_remove ( rootdev ); + return rc; +} + +/** + * Remove PCI root bus + * + * @v rootdev PCI bus root device + */ +static void pcibus_remove ( struct root_device *rootdev ) { + struct pci_device *pci; + struct pci_device *tmp; + + list_for_each_entry_safe ( pci, tmp, &rootdev->dev.children, + dev.siblings ) { + pci_remove ( pci ); + list_del ( &pci->dev.siblings ); + free ( pci ); + } +} + +/** PCI bus root device driver */ +static struct root_driver pci_root_driver = { + .probe = pcibus_probe, + .remove = pcibus_remove, +}; + +/** PCI bus root device */ +struct root_device pci_root_device __root_device = { + .dev = { .name = "PCI" }, + .driver = &pci_root_driver, +}; |