diff options
Diffstat (limited to 'arch/xtensa/lib/pci-auto.c')
| -rw-r--r-- | arch/xtensa/lib/pci-auto.c | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/arch/xtensa/lib/pci-auto.c b/arch/xtensa/lib/pci-auto.c new file mode 100644 index 00000000..a71733ae --- /dev/null +++ b/arch/xtensa/lib/pci-auto.c @@ -0,0 +1,352 @@ +/* + * 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> + * + * 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. + */ + +#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) + * + */ + + +/* define DEBUG to print some debugging messages. */ + +#undef DEBUG + +#ifdef DEBUG +# define DBG(x...) printk(x) +#else +# define DBG(x...) +#endif + +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; + DBG("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; + DBG("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); + + DBG("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; + + DBG("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; + + DBG("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; + + } + + +#if 0 + /* Skip legacy mode IDE controller */ + + if ((pci_class >> 16) == PCI_CLASS_STORAGE_IDE) { + + unsigned char prg_iface; + pci_read_config_byte(dev, PCI_CLASS_PROG, &prg_iface); + + if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) { + DBG("PCI Autoconfig: Skipping legacy mode " + "IDE controller\n"); + continue; + } + } +#endif + + /* + * 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 */ + DBG("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; +} + + + + + |