cregit-Linux how code gets into the kernel

Release 4.14 arch/xtensa/kernel/pci.c

/*
 * arch/xtensa/kernel/pci.c
 *
 * PCI bios-type initialisation for PCI machines
 *
 * 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) 2001-2005 Tensilica Inc.
 *
 * Based largely on work from Cort (ppc/kernel/pci.c)
 * IO functions copied from sparc.
 *
 * Chris Zankel <chris@zankel.net>
 *
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/bootmem.h>

#include <asm/pci-bridge.h>
#include <asm/platform.h>


#undef DEBUG

#ifdef DEBUG

#define DBG(x...) printk(x)
#else

#define DBG(x...)
#endif

/* PCI Controller */


/*
 * pcibios_alloc_controller
 * pcibios_enable_device
 * pcibios_fixups
 * pcibios_align_resource
 * pcibios_fixup_bus
 * pci_bus_add_device
 * pci_mmap_page_range
 */


struct pci_controller* pci_ctrl_head;

struct pci_controller** pci_ctrl_tail = &pci_ctrl_head;


static int pci_bus_count;

/*
 * 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; resource_size_t start = res->start; if (res->flags & IORESOURCE_IO) { if (size > 0x100) { pr_err("PCI: I/O Region %s/%d too large (%u bytes)\n", pci_name(dev), dev->resource - res, size); } if (start & 0x300) start = (start + 0x3ff) & ~0x3ff; } return start; }

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PersonTokensPropCommitsCommitProp
Chris Zankel7582.42%233.33%
Dominik Brodowski1213.19%233.33%
Max Filippov22.20%116.67%
Greg Kroah-Hartman22.20%116.67%
Total91100.00%6100.00%


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<6; idx++) { r = &dev->resource[idx]; if (!r->start && r->end) { printk (KERN_ERR "PCI: Device %s not available because " "of resource collisions\n", pci_name(dev)); return -EINVAL; } if (r->flags & IORESOURCE_IO) cmd |= PCI_COMMAND_IO; if (r->flags & IORESOURCE_MEM) cmd |= PCI_COMMAND_MEMORY; } if (dev->resource[PCI_ROM_RESOURCE].start) cmd |= PCI_COMMAND_MEMORY; if (cmd != old_cmd) { printk("PCI: Enabling device %s (%04x -> %04x)\n", pci_name(dev), old_cmd, cmd); pci_write_config_word(dev, PCI_COMMAND, cmd); } return 0; }

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Chris Zankel167100.00%2100.00%
Total167100.00%2100.00%


struct pci_controller * __init pcibios_alloc_controller(void) { struct pci_controller *pci_ctrl; pci_ctrl = (struct pci_controller *)alloc_bootmem(sizeof(*pci_ctrl)); memset(pci_ctrl, 0, sizeof(struct pci_controller)); *pci_ctrl_tail = pci_ctrl; pci_ctrl_tail = &pci_ctrl->next; return pci_ctrl; }

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Chris Zankel59100.00%1100.00%
Total59100.00%1100.00%


static void __init pci_controller_apertures(struct pci_controller *pci_ctrl, struct list_head *resources) { struct resource *res; unsigned long io_offset; int i; io_offset = (unsigned long)pci_ctrl->io_space.base; res = &pci_ctrl->io_resource; if (!res->flags) { if (io_offset) printk (KERN_ERR "I/O resource not set for host" " bridge %d\n", pci_ctrl->index); res->start = 0; res->end = IO_SPACE_LIMIT; res->flags = IORESOURCE_IO; } res->start += io_offset; res->end += io_offset; pci_add_resource_offset(resources, res, io_offset); for (i = 0; i < 3; i++) { res = &pci_ctrl->mem_resources[i]; if (!res->flags) { if (i > 0) continue; printk(KERN_ERR "Memory resource not set for " "host bridge %d\n", pci_ctrl->index); res->start = 0; res->end = ~0U; res->flags = IORESOURCE_MEM; } pci_add_resource(resources, res); } }

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PersonTokensPropCommitsCommitProp
Chris Zankel16687.83%133.33%
Björn Helgaas2312.17%266.67%
Total189100.00%3100.00%


static int __init pcibios_init(void) { struct pci_controller *pci_ctrl; struct list_head resources; struct pci_bus *bus; int next_busno = 0, ret; printk("PCI: Probing PCI hardware\n"); /* Scan all of the recorded PCI controllers. */ for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) { pci_ctrl->last_busno = 0xff; INIT_LIST_HEAD(&resources); pci_controller_apertures(pci_ctrl, &resources); bus = pci_scan_root_bus(NULL, pci_ctrl->first_busno, pci_ctrl->ops, pci_ctrl, &resources); if (!bus) continue; pci_ctrl->bus = bus; pci_ctrl->last_busno = bus->busn_res.end; if (next_busno <= pci_ctrl->last_busno) next_busno = pci_ctrl->last_busno+1; } pci_bus_count = next_busno; ret = platform_pcibios_fixup(); if (ret) return ret; for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) { if (pci_ctrl->bus) pci_bus_add_devices(pci_ctrl->bus); } return 0; }

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Björn Helgaas12067.42%125.00%
Yijing Wang4927.53%125.00%
Chris Zankel63.37%125.00%
Yinghai Lu31.69%125.00%
Total178100.00%4100.00%

subsys_initcall(pcibios_init);
void pcibios_fixup_bus(struct pci_bus *bus) { if (bus->parent) { /* This is a subordinate bridge */ pci_read_bridge_bases(bus); } }

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Björn Helgaas24100.00%2100.00%
Total24100.00%2100.00%


void pcibios_set_master(struct pci_dev *dev) { /* No special bus mastering setup handling */ }

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Myron Stowe11100.00%1100.00%
Total11100.00%1100.00%


int pcibios_enable_device(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<6; idx++) { r = &dev->resource[idx]; if (!r->start && r->end) { printk(KERN_ERR "PCI: Device %s not available because " "of resource collisions\n", pci_name(dev)); return -EINVAL; } if (r->flags & IORESOURCE_IO) cmd |= PCI_COMMAND_IO; if (r->flags & IORESOURCE_MEM) cmd |= PCI_COMMAND_MEMORY; } if (cmd != old_cmd) { printk("PCI: Enabling device %s (%04x -> %04x)\n", pci_name(dev), old_cmd, cmd); pci_write_config_word(dev, PCI_COMMAND, cmd); } return 0; }

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Chris Zankel152100.00%2100.00%
Total152100.00%2100.00%

#ifdef CONFIG_PROC_FS /* * Return the index of the PCI controller for device pdev. */
int pci_controller_num(struct pci_dev *dev) { struct pci_controller *pci_ctrl = (struct pci_controller*) dev->sysdata; return pci_ctrl->index; }

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Chris Zankel29100.00%1100.00%
Total29100.00%1100.00%

#endif /* CONFIG_PROC_FS */ /* * Platform support for /proc/bus/pci/X/Y mmap()s, * modelled on the sparc64 implementation by Dave Miller. * -- paulus. */ /* * Adjust vm_pgoff of VMA such that it is the physical page offset * corresponding to the 32-bit pci bus offset for DEV requested by the user. * * Basically, the user finds the base address for his device which he wishes * to mmap. They read the 32-bit value from the config space base register, * add whatever PAGE_SIZE multiple offset they wish, and feed this into the * offset parameter of mmap on /proc/bus/pci/XXX for that device. * * Returns negative error code on failure, zero on success. */
static __inline__ int __pci_mmap_make_offset(struct pci_dev *dev, struct vm_area_struct *vma, enum pci_mmap_state mmap_state) { struct pci_controller *pci_ctrl = (struct pci_controller*) dev->sysdata; unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; unsigned long io_offset = 0; int i, res_bit; if (pci_ctrl == 0) return -EINVAL; /* should never happen */ /* If memory, add on the PCI bridge address offset */ if (mmap_state == pci_mmap_mem) { res_bit = IORESOURCE_MEM; } else { io_offset = (unsigned long)pci_ctrl->io_space.base; offset += io_offset; res_bit = IORESOURCE_IO; } /* * Check that the offset requested corresponds to one of the * resources of the device. */ for (i = 0; i <= PCI_ROM_RESOURCE; i++) { struct resource *rp = &dev->resource[i]; int flags = rp->flags; /* treat ROM as memory (should be already) */ if (i == PCI_ROM_RESOURCE) flags |= IORESOURCE_MEM; /* Active and same type? */ if ((flags & res_bit) == 0) continue; /* In the range of this resource? */ if (offset < (rp->start & PAGE_MASK) || offset > rp->end) continue; /* found it! construct the final physical address */ if (mmap_state == pci_mmap_io) offset += pci_ctrl->io_space.start - io_offset; vma->vm_pgoff = offset >> PAGE_SHIFT; return 0; } return -EINVAL; }

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Chris Zankel214100.00%1100.00%
Total214100.00%1100.00%

/* * Perform the actual remap of the pages for a PCI device mapping, as * appropriate for this architecture. The region in the process to map * is described by vm_start and vm_end members of VMA, the base physical * address is found in vm_pgoff. * The pci device structure is provided so that architectures may make mapping * decisions on a per-device or per-bus basis. * * Returns a negative error code on failure, zero on success. */
int pci_mmap_page_range(struct pci_dev *dev, int bar, struct vm_area_struct *vma, enum pci_mmap_state mmap_state, int write_combine) { int ret; ret = __pci_mmap_make_offset(dev, vma, mmap_state); if (ret < 0) return ret; vma->vm_page_prot = pgprot_device(vma->vm_page_prot); ret = io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, vma->vm_end - vma->vm_start,vma->vm_page_prot); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Chris Zankel7988.76%250.00%
David Woodhouse1011.24%250.00%
Total89100.00%4100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Chris Zankel103279.69%317.65%
Björn Helgaas17213.28%317.65%
Yijing Wang493.78%15.88%
Dominik Brodowski120.93%211.76%
Myron Stowe120.93%211.76%
David Woodhouse100.77%211.76%
Yinghai Lu30.23%15.88%
Max Filippov20.15%15.88%
Greg Kroah-Hartman20.15%15.88%
Uwe Zeisberger10.08%15.88%
Total1295100.00%17100.00%
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