Merge remote-tracking branch 's390/features'
[deliverable/linux.git] / arch / x86 / pci / intel_mid_pci.c
CommitLineData
a712ffbc 1/*
05454c26 2 * Intel MID PCI support
a712ffbc
JB
3 * Copyright (c) 2008 Intel Corporation
4 * Jesse Barnes <jesse.barnes@intel.com>
5 *
6 * Moorestown has an interesting PCI implementation:
7 * - configuration space is memory mapped (as defined by MCFG)
8 * - Lincroft devices also have a real, type 1 configuration space
9 * - Early Lincroft silicon has a type 1 access bug that will cause
10 * a hang if non-existent devices are accessed
11 * - some devices have the "fixed BAR" capability, which means
12 * they can't be relocated or modified; check for that during
13 * BAR sizing
14 *
15 * So, we use the MCFG space for all reads and writes, but also send
16 * Lincroft writes to type 1 space. But only read/write if the device
17 * actually exists, otherwise return all 1s for reads and bit bucket
18 * the writes.
19 */
20
21#include <linux/sched.h>
22#include <linux/pci.h>
23#include <linux/ioport.h>
24#include <linux/init.h>
25#include <linux/dmi.h>
7cc24e12
VM
26#include <linux/acpi.h>
27#include <linux/io.h>
28#include <linux/smp.h>
a712ffbc 29
a712ffbc 30#include <asm/segment.h>
a712ffbc
JB
31#include <asm/pci_x86.h>
32#include <asm/hw_irq.h>
33#include <asm/io_apic.h>
bc20aa48 34#include <asm/intel-mid.h>
a712ffbc
JB
35
36#define PCIE_CAP_OFFSET 0x100
37
39d9b77b 38/* Quirks for the listed devices */
707a605b
AS
39#define PCI_DEVICE_ID_INTEL_MRFLD_MMC 0x1190
40#define PCI_DEVICE_ID_INTEL_MRFLD_HSU 0x1191
39d9b77b 41
a712ffbc
JB
42/* Fixed BAR fields */
43#define PCIE_VNDR_CAP_ID_FIXED_BAR 0x00 /* Fixed BAR (TBD) */
44#define PCI_FIXED_BAR_0_SIZE 0x04
45#define PCI_FIXED_BAR_1_SIZE 0x08
46#define PCI_FIXED_BAR_2_SIZE 0x0c
47#define PCI_FIXED_BAR_3_SIZE 0x10
48#define PCI_FIXED_BAR_4_SIZE 0x14
49#define PCI_FIXED_BAR_5_SIZE 0x1c
50
7cc24e12 51static int pci_soc_mode;
823806ff 52
a712ffbc
JB
53/**
54 * fixed_bar_cap - return the offset of the fixed BAR cap if found
55 * @bus: PCI bus
56 * @devfn: device in question
57 *
58 * Look for the fixed BAR cap on @bus and @devfn, returning its offset
59 * if found or 0 otherwise.
60 */
61static int fixed_bar_cap(struct pci_bus *bus, unsigned int devfn)
62{
63 int pos;
64 u32 pcie_cap = 0, cap_data;
65
66 pos = PCIE_CAP_OFFSET;
c5411382
JP
67
68 if (!raw_pci_ext_ops)
69 return 0;
70
a712ffbc
JB
71 while (pos) {
72 if (raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
73 devfn, pos, 4, &pcie_cap))
74 return 0;
75
f82c3d71
JP
76 if (PCI_EXT_CAP_ID(pcie_cap) == 0x0000 ||
77 PCI_EXT_CAP_ID(pcie_cap) == 0xffff)
78 break;
a712ffbc
JB
79
80 if (PCI_EXT_CAP_ID(pcie_cap) == PCI_EXT_CAP_ID_VNDR) {
81 raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
82 devfn, pos + 4, 4, &cap_data);
83 if ((cap_data & 0xffff) == PCIE_VNDR_CAP_ID_FIXED_BAR)
84 return pos;
85 }
86
f82c3d71 87 pos = PCI_EXT_CAP_NEXT(pcie_cap);
a712ffbc
JB
88 }
89
90 return 0;
91}
92
93static int pci_device_update_fixed(struct pci_bus *bus, unsigned int devfn,
94 int reg, int len, u32 val, int offset)
95{
96 u32 size;
97 unsigned int domain, busnum;
98 int bar = (reg - PCI_BASE_ADDRESS_0) >> 2;
99
100 domain = pci_domain_nr(bus);
101 busnum = bus->number;
102
103 if (val == ~0 && len == 4) {
104 unsigned long decode;
105
106 raw_pci_ext_ops->read(domain, busnum, devfn,
107 offset + 8 + (bar * 4), 4, &size);
108
109 /* Turn the size into a decode pattern for the sizing code */
110 if (size) {
111 decode = size - 1;
112 decode |= decode >> 1;
113 decode |= decode >> 2;
114 decode |= decode >> 4;
115 decode |= decode >> 8;
116 decode |= decode >> 16;
117 decode++;
118 decode = ~(decode - 1);
119 } else {
e4af4268 120 decode = 0;
a712ffbc
JB
121 }
122
123 /*
124 * If val is all ones, the core code is trying to size the reg,
125 * so update the mmconfig space with the real size.
126 *
127 * Note: this assumes the fixed size we got is a power of two.
128 */
129 return raw_pci_ext_ops->write(domain, busnum, devfn, reg, 4,
130 decode);
131 }
132
133 /* This is some other kind of BAR write, so just do it. */
134 return raw_pci_ext_ops->write(domain, busnum, devfn, reg, len, val);
135}
136
137/**
138 * type1_access_ok - check whether to use type 1
139 * @bus: bus number
140 * @devfn: device & function in question
141 *
142 * If the bus is on a Lincroft chip and it exists, or is not on a Lincroft at
143 * all, the we can go ahead with any reads & writes. If it's on a Lincroft,
144 * but doesn't exist, avoid the access altogether to keep the chip from
145 * hanging.
146 */
147static bool type1_access_ok(unsigned int bus, unsigned int devfn, int reg)
148{
7cc24e12
VM
149 /*
150 * This is a workaround for A0 LNC bug where PCI status register does
a712ffbc
JB
151 * not have new CAP bit set. can not be written by SW either.
152 *
153 * PCI header type in real LNC indicates a single function device, this
154 * will prevent probing other devices under the same function in PCI
155 * shim. Therefore, use the header type in shim instead.
156 */
157 if (reg >= 0x100 || reg == PCI_STATUS || reg == PCI_HEADER_TYPE)
6c21b176 158 return false;
f3f01175
BH
159 if (bus == 0 && (devfn == PCI_DEVFN(2, 0)
160 || devfn == PCI_DEVFN(0, 0)
161 || devfn == PCI_DEVFN(3, 0)))
6c21b176
FW
162 return true;
163 return false; /* Langwell on others */
a712ffbc
JB
164}
165
166static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
167 int size, u32 *value)
168{
169 if (type1_access_ok(bus->number, devfn, where))
170 return pci_direct_conf1.read(pci_domain_nr(bus), bus->number,
171 devfn, where, size, value);
172 return raw_pci_ext_ops->read(pci_domain_nr(bus), bus->number,
173 devfn, where, size, value);
174}
175
176static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
177 int size, u32 value)
178{
179 int offset;
180
7cc24e12
VM
181 /*
182 * On MRST, there is no PCI ROM BAR, this will cause a subsequent read
a712ffbc
JB
183 * to ROM BAR return 0 then being ignored.
184 */
185 if (where == PCI_ROM_ADDRESS)
186 return 0;
187
188 /*
189 * Devices with fixed BARs need special handling:
190 * - BAR sizing code will save, write ~0, read size, restore
191 * - so writes to fixed BARs need special handling
192 * - other writes to fixed BAR devices should go through mmconfig
193 */
194 offset = fixed_bar_cap(bus, devfn);
195 if (offset &&
196 (where >= PCI_BASE_ADDRESS_0 && where <= PCI_BASE_ADDRESS_5)) {
197 return pci_device_update_fixed(bus, devfn, where, size, value,
198 offset);
199 }
200
201 /*
202 * On Moorestown update both real & mmconfig space
203 * Note: early Lincroft silicon can't handle type 1 accesses to
204 * non-existent devices, so just eat the write in that case.
205 */
206 if (type1_access_ok(bus->number, devfn, where))
207 return pci_direct_conf1.write(pci_domain_nr(bus), bus->number,
208 devfn, where, size, value);
209 return raw_pci_ext_ops->write(pci_domain_nr(bus), bus->number, devfn,
210 where, size, value);
211}
212
712b6aa8 213static int intel_mid_pci_irq_enable(struct pci_dev *dev)
a712ffbc 214{
c4d05a2c 215 struct irq_alloc_info info;
ecc527d5 216 int polarity;
2a61c8ea 217 int ret;
a712ffbc 218
67b4eab9 219 if (dev->irq_managed && dev->irq > 0)
cffe0a2b
JL
220 return 0;
221
39d9b77b
AS
222 switch (intel_mid_identify_cpu()) {
223 case INTEL_MID_CPU_CHIP_TANGIER:
5054e1e6 224 polarity = IOAPIC_POL_HIGH;
39d9b77b
AS
225
226 /* Special treatment for IRQ0 */
227 if (dev->irq == 0) {
bb275705
AS
228 /*
229 * Skip HS UART common registers device since it has
230 * IRQ0 assigned and not used by the kernel.
231 */
707a605b 232 if (dev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU)
bb275705 233 return -EBUSY;
39d9b77b
AS
234 /*
235 * TNG has IRQ0 assigned to eMMC controller. But there
236 * are also other devices with bogus PCI configuration
237 * that have IRQ0 assigned. This check ensures that
bb275705
AS
238 * eMMC gets it. The rest of devices still could be
239 * enabled without interrupt line being allocated.
39d9b77b 240 */
707a605b 241 if (dev->device != PCI_DEVICE_ID_INTEL_MRFLD_MMC)
bb275705 242 return 0;
39d9b77b
AS
243 }
244 break;
245 default:
5054e1e6 246 polarity = IOAPIC_POL_LOW;
39d9b77b
AS
247 break;
248 }
249
c4d05a2c 250 ioapic_set_alloc_attr(&info, dev_to_node(&dev->dev), 1, polarity);
a712ffbc 251
7cc24e12
VM
252 /*
253 * MRST only have IOAPIC, the PCI irq lines are 1:1 mapped to
a712ffbc
JB
254 * IOAPIC RTE entries, so we just enable RTE for the device.
255 */
2a61c8ea
AS
256 ret = mp_map_gsi_to_irq(dev->irq, IOAPIC_MAP_ALLOC, &info);
257 if (ret < 0)
258 return ret;
1b5d3e00 259
cffe0a2b
JL
260 dev->irq_managed = 1;
261
a712ffbc
JB
262 return 0;
263}
264
8a3e533d
JL
265static void intel_mid_pci_irq_disable(struct pci_dev *dev)
266{
6c777e87
BH
267 if (!mp_should_keep_irq(&dev->dev) && dev->irq_managed &&
268 dev->irq > 0) {
8a3e533d 269 mp_unmap_irq(dev->irq);
cffe0a2b
JL
270 dev->irq_managed = 0;
271 }
8a3e533d
JL
272}
273
0abbdea1 274static struct pci_ops intel_mid_pci_ops = {
a712ffbc
JB
275 .read = pci_read,
276 .write = pci_write,
277};
278
279/**
712b6aa8 280 * intel_mid_pci_init - installs intel_mid_pci_ops
a712ffbc
JB
281 *
282 * Moorestown has an interesting PCI implementation (see above).
283 * Called when the early platform detection installs it.
284 */
712b6aa8 285int __init intel_mid_pci_init(void)
a712ffbc 286{
7cc24e12 287 pr_info("Intel MID platform detected, using MID PCI ops\n");
a712ffbc 288 pci_mmcfg_late_init();
712b6aa8 289 pcibios_enable_irq = intel_mid_pci_irq_enable;
8a3e533d 290 pcibios_disable_irq = intel_mid_pci_irq_disable;
712b6aa8 291 pci_root_ops = intel_mid_pci_ops;
823806ff 292 pci_soc_mode = 1;
a712ffbc
JB
293 /* Continue with standard init */
294 return 1;
295}
296
7cc24e12
VM
297/*
298 * Langwell devices are not true PCI devices; they are not subject to 10 ms
299 * d3 to d0 delay required by PCI spec.
990a30c5 300 */
a18e3690 301static void pci_d3delay_fixup(struct pci_dev *dev)
990a30c5 302{
7cc24e12
VM
303 /*
304 * PCI fixups are effectively decided compile time. If we have a dual
305 * SoC/non-SoC kernel we don't want to mangle d3 on non-SoC devices.
306 */
307 if (!pci_soc_mode)
308 return;
309 /*
310 * True PCI devices in Lincroft should allow type 1 access, the rest
311 * are Langwell fake PCI devices.
990a30c5
JP
312 */
313 if (type1_access_ok(dev->bus->number, dev->devfn, PCI_DEVICE_ID))
314 return;
315 dev->d3_delay = 0;
316}
317DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_d3delay_fixup);
318
e99a0745 319static void mid_power_off_one_device(struct pci_dev *dev)
990a30c5 320{
5823d089
AS
321 u16 pmcsr;
322
323 /*
324 * Update current state first, otherwise PCI core enforces PCI_D0 in
325 * pci_set_power_state() for devices which status was PCI_UNKNOWN.
326 */
327 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
328 dev->current_state = (pci_power_t __force)(pmcsr & PCI_PM_CTRL_STATE_MASK);
329
8497f696 330 pci_set_power_state(dev, PCI_D3hot);
990a30c5 331}
5823d089 332
e99a0745 333static void mid_power_off_devices(struct pci_dev *dev)
5823d089
AS
334{
335 int id;
336
337 if (!pci_soc_mode)
338 return;
339
340 id = intel_mid_pwr_get_lss_id(dev);
341 if (id < 0)
342 return;
343
344 /*
345 * This sets only PMCSR bits. The actual power off will happen in
346 * arch/x86/platform/intel-mid/pwr.c.
347 */
e99a0745 348 mid_power_off_one_device(dev);
5823d089
AS
349}
350
e99a0745 351DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, mid_power_off_devices);
990a30c5 352
a712ffbc
JB
353/*
354 * Langwell devices reside at fixed offsets, don't try to move them.
355 */
a18e3690 356static void pci_fixed_bar_fixup(struct pci_dev *dev)
a712ffbc
JB
357{
358 unsigned long offset;
359 u32 size;
360 int i;
361
823806ff
AC
362 if (!pci_soc_mode)
363 return;
364
e9b1d5d0
PA
365 /* Must have extended configuration space */
366 if (dev->cfg_size < PCIE_CAP_OFFSET + 4)
367 return;
368
a712ffbc
JB
369 /* Fixup the BAR sizes for fixed BAR devices and make them unmoveable */
370 offset = fixed_bar_cap(dev->bus, dev->devfn);
371 if (!offset || PCI_DEVFN(2, 0) == dev->devfn ||
372 PCI_DEVFN(2, 2) == dev->devfn)
373 return;
374
375 for (i = 0; i < PCI_ROM_RESOURCE; i++) {
376 pci_read_config_dword(dev, offset + 8 + (i * 4), &size);
377 dev->resource[i].end = dev->resource[i].start + size - 1;
378 dev->resource[i].flags |= IORESOURCE_PCI_FIXED;
379 }
380}
381DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_fixed_bar_fixup);
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