1 // PCI config space access functions.
3 // Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
4 // Copyright (C) 2002 MandrakeSoft S.A.
6 // This file may be distributed under the terms of the GNU LGPLv3 license.
8 #include "pci.h" // pci_config_writel
9 #include "ioport.h" // outl
10 #include "util.h" // dprintf
11 #include "config.h" // CONFIG_*
12 #include "pci_regs.h" // PCI_VENDOR_ID
13 #include "pci_ids.h" // PCI_CLASS_DISPLAY_VGA
15 void pci_config_writel(u16 bdf, u32 addr, u32 val)
17 outl(0x80000000 | (bdf << 8) | (addr & 0xfc), PORT_PCI_CMD);
18 outl(val, PORT_PCI_DATA);
21 void pci_config_writew(u16 bdf, u32 addr, u16 val)
23 outl(0x80000000 | (bdf << 8) | (addr & 0xfc), PORT_PCI_CMD);
24 outw(val, PORT_PCI_DATA + (addr & 2));
27 void pci_config_writeb(u16 bdf, u32 addr, u8 val)
29 outl(0x80000000 | (bdf << 8) | (addr & 0xfc), PORT_PCI_CMD);
30 outb(val, PORT_PCI_DATA + (addr & 3));
33 u32 pci_config_readl(u16 bdf, u32 addr)
35 outl(0x80000000 | (bdf << 8) | (addr & 0xfc), PORT_PCI_CMD);
36 return inl(PORT_PCI_DATA);
39 u16 pci_config_readw(u16 bdf, u32 addr)
41 outl(0x80000000 | (bdf << 8) | (addr & 0xfc), PORT_PCI_CMD);
42 return inw(PORT_PCI_DATA + (addr & 2));
45 u8 pci_config_readb(u16 bdf, u32 addr)
47 outl(0x80000000 | (bdf << 8) | (addr & 0xfc), PORT_PCI_CMD);
48 return inb(PORT_PCI_DATA + (addr & 3));
52 pci_next(int bdf, int *pmax)
54 if (pci_bdf_to_fn(bdf) == 1
55 && (pci_config_readb(bdf-1, PCI_HEADER_TYPE) & 0x80) == 0)
56 // Last found device wasn't a multi-function device - skip to
63 if (CONFIG_PCI_ROOT1 && bdf <= (CONFIG_PCI_ROOT1 << 8))
64 bdf = CONFIG_PCI_ROOT1 << 8;
65 else if (CONFIG_PCI_ROOT2 && bdf <= (CONFIG_PCI_ROOT2 << 8))
66 bdf = CONFIG_PCI_ROOT2 << 8;
69 *pmax = max = bdf + 0x0100;
72 u16 v = pci_config_readw(bdf, PCI_VENDOR_ID);
73 if (v != 0x0000 && v != 0xffff)
77 if (pci_bdf_to_fn(bdf) == 0)
83 // Check if found device is a bridge.
84 u32 v = pci_config_readb(bdf, PCI_HEADER_TYPE);
86 if (v == PCI_HEADER_TYPE_BRIDGE || v == PCI_HEADER_TYPE_CARDBUS) {
87 v = pci_config_readl(bdf, PCI_PRIMARY_BUS);
88 int newmax = (v & 0xff00) + 0x0100;
96 // Find a vga device with legacy address decoding enabled.
100 int bdf = 0x0000, max = 0x0100;
103 if (CONFIG_PCI_ROOT1 && bdf <= (CONFIG_PCI_ROOT1 << 8))
104 bdf = CONFIG_PCI_ROOT1 << 8;
105 else if (CONFIG_PCI_ROOT2 && bdf <= (CONFIG_PCI_ROOT2 << 8))
106 bdf = CONFIG_PCI_ROOT2 << 8;
112 u16 cls = pci_config_readw(bdf, PCI_CLASS_DEVICE);
113 if (cls == 0x0000 || cls == 0xffff) {
114 // Device not present.
115 if (pci_bdf_to_fn(bdf) == 0)
121 if (cls == PCI_CLASS_DISPLAY_VGA) {
122 u16 cmd = pci_config_readw(bdf, PCI_COMMAND);
123 if (cmd & PCI_COMMAND_IO && cmd & PCI_COMMAND_MEMORY)
124 // Found active vga card
128 // Check if device is a bridge.
129 u8 hdr = pci_config_readb(bdf, PCI_HEADER_TYPE);
131 if (ht == PCI_HEADER_TYPE_BRIDGE || ht == PCI_HEADER_TYPE_CARDBUS) {
132 u32 ctrl = pci_config_readb(bdf, PCI_BRIDGE_CONTROL);
133 if (ctrl & PCI_BRIDGE_CTL_VGA) {
134 // Found a VGA enabled bridge.
135 u32 pbus = pci_config_readl(bdf, PCI_PRIMARY_BUS);
136 bdf = (pbus & 0xff00);
142 if (pci_bdf_to_fn(bdf) == 0 && (hdr & 0x80) == 0)
143 // Last found device wasn't a multi-function device - skip to
151 // Search for a device with the specified vendor and device ids.
153 pci_find_device(u16 vendid, u16 devid)
155 u32 id = (devid << 16) | vendid;
157 foreachpci(bdf, max) {
158 u32 v = pci_config_readl(bdf, PCI_VENDOR_ID);
167 // Search for a device with the specified class id.
169 pci_find_class(u16 classid)
172 foreachpci(bdf, max) {
173 u16 v = pci_config_readw(bdf, PCI_CLASS_DEVICE);
183 pci_set_bus_master(u16 bdf)
185 u16 val = pci_config_readw(bdf, PCI_COMMAND);
186 val |= PCI_COMMAND_MASTER;
187 pci_config_writew(bdf, PCI_COMMAND, val);