x86, efi: Set runtime_version to the EFI spec revision
[linux/fpc-iii.git] / arch / sh / drivers / pci / fixups-sdk7786.c
blob36eb6fc3c18abd883f1257b52cd9edf65e6f3ff3
1 /*
2 * SDK7786 FPGA PCIe mux handling
4 * Copyright (C) 2010 Paul Mundt
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10 #define pr_fmt(fmt) "PCI: " fmt
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/pci.h>
15 #include <mach/fpga.h>
18 * The SDK7786 FPGA supports mangling of most of the slots in some way or
19 * another. Slots 3/4 are special in that only one can be supported at a
20 * time, and both appear on port 3 to the PCI bus scan. Enabling slot 4
21 * (the horizontal edge connector) will disable slot 3 entirely.
23 * Misconfigurations can be detected through the FPGA via the slot
24 * resistors to determine card presence. Hotplug remains unsupported.
26 static unsigned int slot4en __initdata;
28 char *__init pcibios_setup(char *str)
30 if (strcmp(str, "slot4en") == 0) {
31 slot4en = 1;
32 return NULL;
35 return str;
38 static int __init sdk7786_pci_init(void)
40 u16 data = fpga_read_reg(PCIECR);
43 * Enable slot #4 if it's been specified on the command line.
45 * Optionally reroute if slot #4 has a card present while slot #3
46 * does not, regardless of command line value.
48 * Card presence is logically inverted.
50 slot4en ?: (!(data & PCIECR_PRST4) && (data & PCIECR_PRST3));
51 if (slot4en) {
52 pr_info("Activating PCIe slot#4 (disabling slot#3)\n");
54 data &= ~PCIECR_PCIEMUX1;
55 fpga_write_reg(data, PCIECR);
57 /* Warn about forced rerouting if slot#3 is occupied */
58 if ((data & PCIECR_PRST3) == 0) {
59 pr_warning("Unreachable card detected in slot#3\n");
60 return -EBUSY;
62 } else
63 pr_info("PCIe slot#4 disabled\n");
65 return 0;
67 postcore_initcall(sdk7786_pci_init);