2 * PCI Backend - Handles the virtual fields in the configuration space headers.
4 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 #include <linux/kernel.h>
10 #include <linux/pci.h>
12 #include "conf_space.h"
24 #define is_enable_cmd(value) ((value)&(PCI_COMMAND_MEMORY|PCI_COMMAND_IO))
25 #define is_master_cmd(value) ((value)&PCI_COMMAND_MASTER)
27 /* Bits guests are allowed to control in permissive mode. */
28 #define PCI_COMMAND_GUEST (PCI_COMMAND_MASTER|PCI_COMMAND_SPECIAL| \
29 PCI_COMMAND_INVALIDATE|PCI_COMMAND_VGA_PALETTE| \
30 PCI_COMMAND_WAIT|PCI_COMMAND_FAST_BACK)
32 static void *command_init(struct pci_dev *dev, int offset)
34 struct pci_cmd_info *cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
38 return ERR_PTR(-ENOMEM);
40 err = pci_read_config_word(dev, PCI_COMMAND, &cmd->val);
49 static int command_read(struct pci_dev *dev, int offset, u16 *value, void *data)
51 int ret = pci_read_config_word(dev, offset, value);
52 const struct pci_cmd_info *cmd = data;
54 *value &= PCI_COMMAND_GUEST;
55 *value |= cmd->val & ~PCI_COMMAND_GUEST;
60 static int command_write(struct pci_dev *dev, int offset, u16 value, void *data)
62 struct xen_pcibk_dev_data *dev_data;
65 struct pci_cmd_info *cmd = data;
67 dev_data = pci_get_drvdata(dev);
68 if (!pci_is_enabled(dev) && is_enable_cmd(value)) {
69 if (unlikely(verbose_request))
70 printk(KERN_DEBUG DRV_NAME ": %s: enable\n",
72 err = pci_enable_device(dev);
76 dev_data->enable_intx = 1;
77 } else if (pci_is_enabled(dev) && !is_enable_cmd(value)) {
78 if (unlikely(verbose_request))
79 printk(KERN_DEBUG DRV_NAME ": %s: disable\n",
81 pci_disable_device(dev);
83 dev_data->enable_intx = 0;
86 if (!dev->is_busmaster && is_master_cmd(value)) {
87 if (unlikely(verbose_request))
88 printk(KERN_DEBUG DRV_NAME ": %s: set bus master\n",
91 } else if (dev->is_busmaster && !is_master_cmd(value)) {
92 if (unlikely(verbose_request))
93 printk(KERN_DEBUG DRV_NAME ": %s: clear bus master\n",
95 pci_clear_master(dev);
98 if (!(cmd->val & PCI_COMMAND_INVALIDATE) &&
99 (value & PCI_COMMAND_INVALIDATE)) {
100 if (unlikely(verbose_request))
102 DRV_NAME ": %s: enable memory-write-invalidate\n",
104 err = pci_set_mwi(dev);
106 pr_warn("%s: cannot enable memory-write-invalidate (%d)\n",
108 value &= ~PCI_COMMAND_INVALIDATE;
110 } else if ((cmd->val & PCI_COMMAND_INVALIDATE) &&
111 !(value & PCI_COMMAND_INVALIDATE)) {
112 if (unlikely(verbose_request))
114 DRV_NAME ": %s: disable memory-write-invalidate\n",
121 if (!xen_pcibk_permissive && (!dev_data || !dev_data->permissive))
124 /* Only allow the guest to control certain bits. */
125 err = pci_read_config_word(dev, offset, &val);
126 if (err || val == value)
129 value &= PCI_COMMAND_GUEST;
130 value |= val & ~PCI_COMMAND_GUEST;
132 return pci_write_config_word(dev, offset, value);
135 static int rom_write(struct pci_dev *dev, int offset, u32 value, void *data)
137 struct pci_bar_info *bar = data;
139 if (unlikely(!bar)) {
140 pr_warn(DRV_NAME ": driver data not found for %s\n",
142 return XEN_PCI_ERR_op_failed;
145 /* A write to obtain the length must happen as a 32-bit write.
146 * This does not (yet) support writing individual bytes
148 if ((value | ~PCI_ROM_ADDRESS_MASK) == ~0U)
152 pci_read_config_dword(dev, offset, &tmpval);
153 if (tmpval != bar->val && value == bar->val) {
154 /* Allow restoration of bar value. */
155 pci_write_config_dword(dev, offset, bar->val);
160 /* Do we need to support enabling/disabling the rom address here? */
165 /* For the BARs, only allow writes which write ~0 or
166 * the correct resource information
167 * (Needed for when the driver probes the resource usage)
169 static int bar_write(struct pci_dev *dev, int offset, u32 value, void *data)
171 struct pci_bar_info *bar = data;
172 unsigned int pos = (offset - PCI_BASE_ADDRESS_0) / 4;
173 const struct resource *res = dev->resource;
176 if (unlikely(!bar)) {
177 pr_warn(DRV_NAME ": driver data not found for %s\n",
179 return XEN_PCI_ERR_op_failed;
182 /* A write to obtain the length must happen as a 32-bit write.
183 * This does not (yet) support writing individual bytes
185 if (res[pos].flags & IORESOURCE_IO)
186 mask = ~PCI_BASE_ADDRESS_IO_MASK;
187 else if (pos && (res[pos - 1].flags & IORESOURCE_MEM_64))
190 mask = ~PCI_BASE_ADDRESS_MEM_MASK;
191 if ((value | mask) == ~0U)
195 pci_read_config_dword(dev, offset, &tmpval);
196 if (tmpval != bar->val && value == bar->val) {
197 /* Allow restoration of bar value. */
198 pci_write_config_dword(dev, offset, bar->val);
206 static int bar_read(struct pci_dev *dev, int offset, u32 * value, void *data)
208 struct pci_bar_info *bar = data;
210 if (unlikely(!bar)) {
211 pr_warn(DRV_NAME ": driver data not found for %s\n",
213 return XEN_PCI_ERR_op_failed;
216 *value = bar->which ? bar->len_val : bar->val;
221 static void *bar_init(struct pci_dev *dev, int offset)
224 const struct resource *res = dev->resource;
225 struct pci_bar_info *bar = kzalloc(sizeof(*bar), GFP_KERNEL);
228 return ERR_PTR(-ENOMEM);
230 if (offset == PCI_ROM_ADDRESS || offset == PCI_ROM_ADDRESS1)
231 pos = PCI_ROM_RESOURCE;
233 pos = (offset - PCI_BASE_ADDRESS_0) / 4;
234 if (pos && (res[pos - 1].flags & IORESOURCE_MEM_64)) {
235 bar->val = res[pos - 1].start >> 32;
236 bar->len_val = -resource_size(&res[pos - 1]) >> 32;
241 if (!res[pos].flags ||
242 (res[pos].flags & (IORESOURCE_DISABLED | IORESOURCE_UNSET |
246 bar->val = res[pos].start |
247 (res[pos].flags & PCI_REGION_FLAG_MASK);
248 bar->len_val = -resource_size(&res[pos]) |
249 (res[pos].flags & PCI_REGION_FLAG_MASK);
254 static void bar_reset(struct pci_dev *dev, int offset, void *data)
256 struct pci_bar_info *bar = data;
261 static void bar_release(struct pci_dev *dev, int offset, void *data)
266 static int xen_pcibk_read_vendor(struct pci_dev *dev, int offset,
267 u16 *value, void *data)
269 *value = dev->vendor;
274 static int xen_pcibk_read_device(struct pci_dev *dev, int offset,
275 u16 *value, void *data)
277 *value = dev->device;
282 static int interrupt_read(struct pci_dev *dev, int offset, u8 * value,
285 *value = (u8) dev->irq;
290 static int bist_write(struct pci_dev *dev, int offset, u8 value, void *data)
295 err = pci_read_config_byte(dev, offset, &cur_value);
299 if ((cur_value & ~PCI_BIST_START) == (value & ~PCI_BIST_START)
300 || value == PCI_BIST_START)
301 err = pci_write_config_byte(dev, offset, value);
307 static const struct config_field header_common[] = {
309 .offset = PCI_VENDOR_ID,
311 .u.w.read = xen_pcibk_read_vendor,
314 .offset = PCI_DEVICE_ID,
316 .u.w.read = xen_pcibk_read_device,
319 .offset = PCI_COMMAND,
321 .init = command_init,
322 .release = bar_release,
323 .u.w.read = command_read,
324 .u.w.write = command_write,
327 .offset = PCI_INTERRUPT_LINE,
329 .u.b.read = interrupt_read,
332 .offset = PCI_INTERRUPT_PIN,
334 .u.b.read = xen_pcibk_read_config_byte,
337 /* Any side effects of letting driver domain control cache line? */
338 .offset = PCI_CACHE_LINE_SIZE,
340 .u.b.read = xen_pcibk_read_config_byte,
341 .u.b.write = xen_pcibk_write_config_byte,
344 .offset = PCI_LATENCY_TIMER,
346 .u.b.read = xen_pcibk_read_config_byte,
351 .u.b.read = xen_pcibk_read_config_byte,
352 .u.b.write = bist_write,
357 #define CFG_FIELD_BAR(reg_offset) \
359 .offset = reg_offset, \
362 .reset = bar_reset, \
363 .release = bar_release, \
364 .u.dw.read = bar_read, \
365 .u.dw.write = bar_write, \
368 #define CFG_FIELD_ROM(reg_offset) \
370 .offset = reg_offset, \
373 .reset = bar_reset, \
374 .release = bar_release, \
375 .u.dw.read = bar_read, \
376 .u.dw.write = rom_write, \
379 static const struct config_field header_0[] = {
380 CFG_FIELD_BAR(PCI_BASE_ADDRESS_0),
381 CFG_FIELD_BAR(PCI_BASE_ADDRESS_1),
382 CFG_FIELD_BAR(PCI_BASE_ADDRESS_2),
383 CFG_FIELD_BAR(PCI_BASE_ADDRESS_3),
384 CFG_FIELD_BAR(PCI_BASE_ADDRESS_4),
385 CFG_FIELD_BAR(PCI_BASE_ADDRESS_5),
386 CFG_FIELD_ROM(PCI_ROM_ADDRESS),
390 static const struct config_field header_1[] = {
391 CFG_FIELD_BAR(PCI_BASE_ADDRESS_0),
392 CFG_FIELD_BAR(PCI_BASE_ADDRESS_1),
393 CFG_FIELD_ROM(PCI_ROM_ADDRESS1),
397 int xen_pcibk_config_header_add_fields(struct pci_dev *dev)
401 err = xen_pcibk_config_add_fields(dev, header_common);
405 switch (dev->hdr_type) {
406 case PCI_HEADER_TYPE_NORMAL:
407 err = xen_pcibk_config_add_fields(dev, header_0);
410 case PCI_HEADER_TYPE_BRIDGE:
411 err = xen_pcibk_config_add_fields(dev, header_1);
416 pr_err("%s: Unsupported header type %d!\n",
417 pci_name(dev), dev->hdr_type);