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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * leon_pci.c: LEON Host PCI support
4 *
5 * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
6 *
7 * Code is partially derived from pcic.c
8 */
9
10#include <linux/of_device.h>
11#include <linux/kernel.h>
12#include <linux/pci.h>
13#include <linux/export.h>
14#include <asm/leon.h>
15#include <asm/leon_pci.h>
16
17/* The LEON architecture does not rely on a BIOS or bootloader to setup
18 * PCI for us. The Linux generic routines are used to setup resources,
19 * reset values of configuration-space register settings are preserved.
20 *
21 * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
22 * accessed through a Window which is translated to low 64KB in PCI space, the
23 * first 4KB is not used so 60KB is available.
24 */
25void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
26{
27 LIST_HEAD(resources);
28 struct pci_bus *root_bus;
29 struct pci_host_bridge *bridge;
30 int ret;
31
32 bridge = pci_alloc_host_bridge(0);
33 if (!bridge)
34 return;
35
36 pci_add_resource_offset(&resources, &info->io_space,
37 info->io_space.start - 0x1000);
38 pci_add_resource(&resources, &info->mem_space);
39 info->busn.flags = IORESOURCE_BUS;
40 pci_add_resource(&resources, &info->busn);
41
42 list_splice_init(&resources, &bridge->windows);
43 bridge->dev.parent = &ofdev->dev;
44 bridge->sysdata = info;
45 bridge->busnr = 0;
46 bridge->ops = info->ops;
47 bridge->swizzle_irq = pci_common_swizzle;
48 bridge->map_irq = info->map_irq;
49
50 ret = pci_scan_root_bus_bridge(bridge);
51 if (ret) {
52 pci_free_host_bridge(bridge);
53 return;
54 }
55
56 root_bus = bridge->bus;
57
58 /* Assign devices with resources */
59 pci_assign_unassigned_resources();
60 pci_bus_add_devices(root_bus);
61}
62
63int pcibios_enable_device(struct pci_dev *dev, int mask)
64{
65 u16 cmd, oldcmd;
66 int i;
67
68 pci_read_config_word(dev, PCI_COMMAND, &cmd);
69 oldcmd = cmd;
70
71 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
72 struct resource *res = &dev->resource[i];
73
74 /* Only set up the requested stuff */
75 if (!(mask & (1<<i)))
76 continue;
77
78 if (res->flags & IORESOURCE_IO)
79 cmd |= PCI_COMMAND_IO;
80 if (res->flags & IORESOURCE_MEM)
81 cmd |= PCI_COMMAND_MEMORY;
82 }
83
84 if (cmd != oldcmd) {
85 pci_info(dev, "enabling device (%04x -> %04x)\n", oldcmd, cmd);
86 pci_write_config_word(dev, PCI_COMMAND, cmd);
87 }
88 return 0;
89}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * leon_pci.c: LEON Host PCI support
4 *
5 * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
6 *
7 * Code is partially derived from pcic.c
8 */
9
10#include <linux/of_device.h>
11#include <linux/kernel.h>
12#include <linux/pci.h>
13#include <linux/export.h>
14#include <asm/leon.h>
15#include <asm/leon_pci.h>
16
17/* The LEON architecture does not rely on a BIOS or bootloader to setup
18 * PCI for us. The Linux generic routines are used to setup resources,
19 * reset values of configuration-space register settings are preserved.
20 *
21 * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
22 * accessed through a Window which is translated to low 64KB in PCI space, the
23 * first 4KB is not used so 60KB is available.
24 */
25void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
26{
27 LIST_HEAD(resources);
28 struct pci_bus *root_bus;
29 struct pci_host_bridge *bridge;
30 int ret;
31
32 bridge = pci_alloc_host_bridge(0);
33 if (!bridge)
34 return;
35
36 pci_add_resource_offset(&resources, &info->io_space,
37 info->io_space.start - 0x1000);
38 pci_add_resource(&resources, &info->mem_space);
39 info->busn.flags = IORESOURCE_BUS;
40 pci_add_resource(&resources, &info->busn);
41
42 list_splice_init(&resources, &bridge->windows);
43 bridge->dev.parent = &ofdev->dev;
44 bridge->sysdata = info;
45 bridge->busnr = 0;
46 bridge->ops = info->ops;
47 bridge->swizzle_irq = pci_common_swizzle;
48 bridge->map_irq = info->map_irq;
49
50 ret = pci_scan_root_bus_bridge(bridge);
51 if (ret) {
52 pci_free_host_bridge(bridge);
53 return;
54 }
55
56 root_bus = bridge->bus;
57
58 /* Assign devices with resources */
59 pci_assign_unassigned_resources();
60 pci_bus_add_devices(root_bus);
61}
62
63int pcibios_enable_device(struct pci_dev *dev, int mask)
64{
65 u16 cmd, oldcmd;
66 int i;
67
68 pci_read_config_word(dev, PCI_COMMAND, &cmd);
69 oldcmd = cmd;
70
71 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
72 struct resource *res = &dev->resource[i];
73
74 /* Only set up the requested stuff */
75 if (!(mask & (1<<i)))
76 continue;
77
78 if (res->flags & IORESOURCE_IO)
79 cmd |= PCI_COMMAND_IO;
80 if (res->flags & IORESOURCE_MEM)
81 cmd |= PCI_COMMAND_MEMORY;
82 }
83
84 if (cmd != oldcmd) {
85 pci_info(dev, "enabling device (%04x -> %04x)\n", oldcmd, cmd);
86 pci_write_config_word(dev, PCI_COMMAND, cmd);
87 }
88 return 0;
89}