ARM: mmp: fix potential NULL dereference
[linux/fpc-iii.git] / arch / alpha / kernel / core_apecs.c
blob708c831efa76594a1cd2299b7d3214f06f3ccc69
1 /*
2 * linux/arch/alpha/kernel/core_apecs.c
4 * Rewritten for Apecs from the lca.c from:
6 * Written by David Mosberger (davidm@cs.arizona.edu) with some code
7 * taken from Dave Rusling's (david.rusling@reo.mts.dec.com) 32-bit
8 * bios code.
10 * Code common to all APECS core logic chips.
13 #define __EXTERN_INLINE inline
14 #include <asm/io.h>
15 #include <asm/core_apecs.h>
16 #undef __EXTERN_INLINE
18 #include <linux/types.h>
19 #include <linux/pci.h>
20 #include <linux/init.h>
22 #include <asm/ptrace.h>
23 #include <asm/smp.h>
24 #include <asm/mce.h>
26 #include "proto.h"
27 #include "pci_impl.h"
30 * NOTE: Herein lie back-to-back mb instructions. They are magic.
31 * One plausible explanation is that the i/o controller does not properly
32 * handle the system transaction. Another involves timing. Ho hum.
36 * BIOS32-style PCI interface:
39 #define DEBUG_CONFIG 0
41 #if DEBUG_CONFIG
42 # define DBGC(args) printk args
43 #else
44 # define DBGC(args)
45 #endif
47 #define vuip volatile unsigned int *
50 * Given a bus, device, and function number, compute resulting
51 * configuration space address and setup the APECS_HAXR2 register
52 * accordingly. It is therefore not safe to have concurrent
53 * invocations to configuration space access routines, but there
54 * really shouldn't be any need for this.
56 * Type 0:
58 * 3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1
59 * 3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
60 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61 * | | | | | | | | | | | | | | | | | | | | | | | |F|F|F|R|R|R|R|R|R|0|0|
62 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
64 * 31:11 Device select bit.
65 * 10:8 Function number
66 * 7:2 Register number
68 * Type 1:
70 * 3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1
71 * 3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
72 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 * | | | | | | | | | | |B|B|B|B|B|B|B|B|D|D|D|D|D|F|F|F|R|R|R|R|R|R|0|1|
74 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76 * 31:24 reserved
77 * 23:16 bus number (8 bits = 128 possible buses)
78 * 15:11 Device number (5 bits)
79 * 10:8 function number
80 * 7:2 register number
82 * Notes:
83 * The function number selects which function of a multi-function device
84 * (e.g., SCSI and Ethernet).
86 * The register selects a DWORD (32 bit) register offset. Hence it
87 * doesn't get shifted by 2 bits as we want to "drop" the bottom two
88 * bits.
91 static int
92 mk_conf_addr(struct pci_bus *pbus, unsigned int device_fn, int where,
93 unsigned long *pci_addr, unsigned char *type1)
95 unsigned long addr;
96 u8 bus = pbus->number;
98 DBGC(("mk_conf_addr(bus=%d ,device_fn=0x%x, where=0x%x,"
99 " pci_addr=0x%p, type1=0x%p)\n",
100 bus, device_fn, where, pci_addr, type1));
102 if (bus == 0) {
103 int device = device_fn >> 3;
105 /* type 0 configuration cycle: */
107 if (device > 20) {
108 DBGC(("mk_conf_addr: device (%d) > 20, returning -1\n",
109 device));
110 return -1;
113 *type1 = 0;
114 addr = (device_fn << 8) | (where);
115 } else {
116 /* type 1 configuration cycle: */
117 *type1 = 1;
118 addr = (bus << 16) | (device_fn << 8) | (where);
120 *pci_addr = addr;
121 DBGC(("mk_conf_addr: returning pci_addr 0x%lx\n", addr));
122 return 0;
125 static unsigned int
126 conf_read(unsigned long addr, unsigned char type1)
128 unsigned long flags;
129 unsigned int stat0, value;
130 unsigned int haxr2 = 0;
132 local_irq_save(flags); /* avoid getting hit by machine check */
134 DBGC(("conf_read(addr=0x%lx, type1=%d)\n", addr, type1));
136 /* Reset status register to avoid losing errors. */
137 stat0 = *(vuip)APECS_IOC_DCSR;
138 *(vuip)APECS_IOC_DCSR = stat0;
139 mb();
140 DBGC(("conf_read: APECS DCSR was 0x%x\n", stat0));
142 /* If Type1 access, must set HAE #2. */
143 if (type1) {
144 haxr2 = *(vuip)APECS_IOC_HAXR2;
145 mb();
146 *(vuip)APECS_IOC_HAXR2 = haxr2 | 1;
147 DBGC(("conf_read: TYPE1 access\n"));
150 draina();
151 mcheck_expected(0) = 1;
152 mcheck_taken(0) = 0;
153 mb();
155 /* Access configuration space. */
157 /* Some SRMs step on these registers during a machine check. */
158 asm volatile("ldl %0,%1; mb; mb" : "=r"(value) : "m"(*(vuip)addr)
159 : "$9", "$10", "$11", "$12", "$13", "$14", "memory");
161 if (mcheck_taken(0)) {
162 mcheck_taken(0) = 0;
163 value = 0xffffffffU;
164 mb();
166 mcheck_expected(0) = 0;
167 mb();
169 #if 1
171 * david.rusling@reo.mts.dec.com. This code is needed for the
172 * EB64+ as it does not generate a machine check (why I don't
173 * know). When we build kernels for one particular platform
174 * then we can make this conditional on the type.
176 draina();
178 /* Now look for any errors. */
179 stat0 = *(vuip)APECS_IOC_DCSR;
180 DBGC(("conf_read: APECS DCSR after read 0x%x\n", stat0));
182 /* Is any error bit set? */
183 if (stat0 & 0xffe0U) {
184 /* If not NDEV, print status. */
185 if (!(stat0 & 0x0800)) {
186 printk("apecs.c:conf_read: got stat0=%x\n", stat0);
189 /* Reset error status. */
190 *(vuip)APECS_IOC_DCSR = stat0;
191 mb();
192 wrmces(0x7); /* reset machine check */
193 value = 0xffffffff;
195 #endif
197 /* If Type1 access, must reset HAE #2 so normal IO space ops work. */
198 if (type1) {
199 *(vuip)APECS_IOC_HAXR2 = haxr2 & ~1;
200 mb();
202 local_irq_restore(flags);
204 return value;
207 static void
208 conf_write(unsigned long addr, unsigned int value, unsigned char type1)
210 unsigned long flags;
211 unsigned int stat0;
212 unsigned int haxr2 = 0;
214 local_irq_save(flags); /* avoid getting hit by machine check */
216 /* Reset status register to avoid losing errors. */
217 stat0 = *(vuip)APECS_IOC_DCSR;
218 *(vuip)APECS_IOC_DCSR = stat0;
219 mb();
221 /* If Type1 access, must set HAE #2. */
222 if (type1) {
223 haxr2 = *(vuip)APECS_IOC_HAXR2;
224 mb();
225 *(vuip)APECS_IOC_HAXR2 = haxr2 | 1;
228 draina();
229 mcheck_expected(0) = 1;
230 mb();
232 /* Access configuration space. */
233 *(vuip)addr = value;
234 mb();
235 mb(); /* magic */
236 mcheck_expected(0) = 0;
237 mb();
239 #if 1
241 * david.rusling@reo.mts.dec.com. This code is needed for the
242 * EB64+ as it does not generate a machine check (why I don't
243 * know). When we build kernels for one particular platform
244 * then we can make this conditional on the type.
246 draina();
248 /* Now look for any errors. */
249 stat0 = *(vuip)APECS_IOC_DCSR;
251 /* Is any error bit set? */
252 if (stat0 & 0xffe0U) {
253 /* If not NDEV, print status. */
254 if (!(stat0 & 0x0800)) {
255 printk("apecs.c:conf_write: got stat0=%x\n", stat0);
258 /* Reset error status. */
259 *(vuip)APECS_IOC_DCSR = stat0;
260 mb();
261 wrmces(0x7); /* reset machine check */
263 #endif
265 /* If Type1 access, must reset HAE #2 so normal IO space ops work. */
266 if (type1) {
267 *(vuip)APECS_IOC_HAXR2 = haxr2 & ~1;
268 mb();
270 local_irq_restore(flags);
273 static int
274 apecs_read_config(struct pci_bus *bus, unsigned int devfn, int where,
275 int size, u32 *value)
277 unsigned long addr, pci_addr;
278 unsigned char type1;
279 long mask;
280 int shift;
282 if (mk_conf_addr(bus, devfn, where, &pci_addr, &type1))
283 return PCIBIOS_DEVICE_NOT_FOUND;
285 mask = (size - 1) * 8;
286 shift = (where & 3) * 8;
287 addr = (pci_addr << 5) + mask + APECS_CONF;
288 *value = conf_read(addr, type1) >> (shift);
289 return PCIBIOS_SUCCESSFUL;
292 static int
293 apecs_write_config(struct pci_bus *bus, unsigned int devfn, int where,
294 int size, u32 value)
296 unsigned long addr, pci_addr;
297 unsigned char type1;
298 long mask;
300 if (mk_conf_addr(bus, devfn, where, &pci_addr, &type1))
301 return PCIBIOS_DEVICE_NOT_FOUND;
303 mask = (size - 1) * 8;
304 addr = (pci_addr << 5) + mask + APECS_CONF;
305 conf_write(addr, value << ((where & 3) * 8), type1);
306 return PCIBIOS_SUCCESSFUL;
309 struct pci_ops apecs_pci_ops =
311 .read = apecs_read_config,
312 .write = apecs_write_config,
315 void
316 apecs_pci_tbi(struct pci_controller *hose, dma_addr_t start, dma_addr_t end)
318 wmb();
319 *(vip)APECS_IOC_TBIA = 0;
320 mb();
323 void __init
324 apecs_init_arch(void)
326 struct pci_controller *hose;
329 * Create our single hose.
332 pci_isa_hose = hose = alloc_pci_controller();
333 hose->io_space = &ioport_resource;
334 hose->mem_space = &iomem_resource;
335 hose->index = 0;
337 hose->sparse_mem_base = APECS_SPARSE_MEM - IDENT_ADDR;
338 hose->dense_mem_base = APECS_DENSE_MEM - IDENT_ADDR;
339 hose->sparse_io_base = APECS_IO - IDENT_ADDR;
340 hose->dense_io_base = 0;
343 * Set up the PCI to main memory translation windows.
345 * Window 1 is direct access 1GB at 1GB
346 * Window 2 is scatter-gather 8MB at 8MB (for isa)
348 hose->sg_isa = iommu_arena_new(hose, 0x00800000, 0x00800000, 0);
349 hose->sg_pci = NULL;
350 __direct_map_base = 0x40000000;
351 __direct_map_size = 0x40000000;
353 *(vuip)APECS_IOC_PB1R = __direct_map_base | 0x00080000;
354 *(vuip)APECS_IOC_PM1R = (__direct_map_size - 1) & 0xfff00000U;
355 *(vuip)APECS_IOC_TB1R = 0;
357 *(vuip)APECS_IOC_PB2R = hose->sg_isa->dma_base | 0x000c0000;
358 *(vuip)APECS_IOC_PM2R = (hose->sg_isa->size - 1) & 0xfff00000;
359 *(vuip)APECS_IOC_TB2R = virt_to_phys(hose->sg_isa->ptes) >> 1;
361 apecs_pci_tbi(hose, 0, -1);
364 * Finally, clear the HAXR2 register, which gets used
365 * for PCI Config Space accesses. That is the way
366 * we want to use it, and we do not want to depend on
367 * what ARC or SRM might have left behind...
369 *(vuip)APECS_IOC_HAXR2 = 0;
370 mb();
373 void
374 apecs_pci_clr_err(void)
376 unsigned int jd;
378 jd = *(vuip)APECS_IOC_DCSR;
379 if (jd & 0xffe0L) {
380 *(vuip)APECS_IOC_SEAR;
381 *(vuip)APECS_IOC_DCSR = jd | 0xffe1L;
382 mb();
383 *(vuip)APECS_IOC_DCSR;
385 *(vuip)APECS_IOC_TBIA = (unsigned int)APECS_IOC_TBIA;
386 mb();
387 *(vuip)APECS_IOC_TBIA;
390 void
391 apecs_machine_check(unsigned long vector, unsigned long la_ptr)
393 struct el_common *mchk_header;
394 struct el_apecs_procdata *mchk_procdata;
395 struct el_apecs_sysdata_mcheck *mchk_sysdata;
397 mchk_header = (struct el_common *)la_ptr;
399 mchk_procdata = (struct el_apecs_procdata *)
400 (la_ptr + mchk_header->proc_offset
401 - sizeof(mchk_procdata->paltemp));
403 mchk_sysdata = (struct el_apecs_sysdata_mcheck *)
404 (la_ptr + mchk_header->sys_offset);
407 /* Clear the error before any reporting. */
408 mb();
409 mb(); /* magic */
410 draina();
411 apecs_pci_clr_err();
412 wrmces(0x7); /* reset machine check pending flag */
413 mb();
415 process_mcheck_info(vector, la_ptr, "APECS",
416 (mcheck_expected(0)
417 && (mchk_sysdata->epic_dcsr & 0x0c00UL)));