xref: /openbmc/linux/arch/alpha/kernel/core_apecs.c (revision 94cdda6b)
1 /*
2  *	linux/arch/alpha/kernel/core_apecs.c
3  *
4  * Rewritten for Apecs from the lca.c from:
5  *
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.
9  *
10  * Code common to all APECS core logic chips.
11  */
12 
13 #define __EXTERN_INLINE inline
14 #include <asm/io.h>
15 #include <asm/core_apecs.h>
16 #undef __EXTERN_INLINE
17 
18 #include <linux/types.h>
19 #include <linux/pci.h>
20 #include <linux/init.h>
21 
22 #include <asm/ptrace.h>
23 #include <asm/smp.h>
24 #include <asm/mce.h>
25 
26 #include "proto.h"
27 #include "pci_impl.h"
28 
29 /*
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.
33  */
34 
35 /*
36  * BIOS32-style PCI interface:
37  */
38 
39 #define DEBUG_CONFIG 0
40 
41 #if DEBUG_CONFIG
42 # define DBGC(args)	printk args
43 #else
44 # define DBGC(args)
45 #endif
46 
47 #define vuip	volatile unsigned int  *
48 
49 /*
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.
55  *
56  * Type 0:
57  *
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  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63  *
64  *	31:11	Device select bit.
65  * 	10:8	Function number
66  * 	 7:2	Register number
67  *
68  * Type 1:
69  *
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  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
75  *
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
81  *
82  * Notes:
83  *	The function number selects which function of a multi-function device
84  *	(e.g., SCSI and Ethernet).
85  *
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.
89  */
90 
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)
94 {
95 	unsigned long addr;
96 	u8 bus = pbus->number;
97 
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));
101 
102 	if (bus == 0) {
103 		int device = device_fn >> 3;
104 
105 		/* type 0 configuration cycle: */
106 
107 		if (device > 20) {
108 			DBGC(("mk_conf_addr: device (%d) > 20, returning -1\n",
109 			      device));
110 			return -1;
111 		}
112 
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);
119 	}
120 	*pci_addr = addr;
121 	DBGC(("mk_conf_addr: returning pci_addr 0x%lx\n", addr));
122 	return 0;
123 }
124 
125 static unsigned int
126 conf_read(unsigned long addr, unsigned char type1)
127 {
128 	unsigned long flags;
129 	unsigned int stat0, value;
130 	unsigned int haxr2 = 0;
131 
132 	local_irq_save(flags);	/* avoid getting hit by machine check */
133 
134 	DBGC(("conf_read(addr=0x%lx, type1=%d)\n", addr, type1));
135 
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));
141 
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"));
148 	}
149 
150 	draina();
151 	mcheck_expected(0) = 1;
152 	mcheck_taken(0) = 0;
153 	mb();
154 
155 	/* Access configuration space.  */
156 
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");
160 
161 	if (mcheck_taken(0)) {
162 		mcheck_taken(0) = 0;
163 		value = 0xffffffffU;
164 		mb();
165 	}
166 	mcheck_expected(0) = 0;
167 	mb();
168 
169 #if 1
170 	/*
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.
175 	 */
176 	draina();
177 
178 	/* Now look for any errors.  */
179 	stat0 = *(vuip)APECS_IOC_DCSR;
180 	DBGC(("conf_read: APECS DCSR after read 0x%x\n", stat0));
181 
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);
187 		}
188 
189 		/* Reset error status.  */
190 		*(vuip)APECS_IOC_DCSR = stat0;
191 		mb();
192 		wrmces(0x7);			/* reset machine check */
193 		value = 0xffffffff;
194 	}
195 #endif
196 
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();
201 	}
202 	local_irq_restore(flags);
203 
204 	return value;
205 }
206 
207 static void
208 conf_write(unsigned long addr, unsigned int value, unsigned char type1)
209 {
210 	unsigned long flags;
211 	unsigned int stat0;
212 	unsigned int haxr2 = 0;
213 
214 	local_irq_save(flags);	/* avoid getting hit by machine check */
215 
216 	/* Reset status register to avoid losing errors.  */
217 	stat0 = *(vuip)APECS_IOC_DCSR;
218 	*(vuip)APECS_IOC_DCSR = stat0;
219 	mb();
220 
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;
226 	}
227 
228 	draina();
229 	mcheck_expected(0) = 1;
230 	mb();
231 
232 	/* Access configuration space.  */
233 	*(vuip)addr = value;
234 	mb();
235 	mb();  /* magic */
236 	mcheck_expected(0) = 0;
237 	mb();
238 
239 #if 1
240 	/*
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.
245 	 */
246 	draina();
247 
248 	/* Now look for any errors.  */
249 	stat0 = *(vuip)APECS_IOC_DCSR;
250 
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);
256 		}
257 
258 		/* Reset error status.  */
259 		*(vuip)APECS_IOC_DCSR = stat0;
260 		mb();
261 		wrmces(0x7);			/* reset machine check */
262 	}
263 #endif
264 
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();
269 	}
270 	local_irq_restore(flags);
271 }
272 
273 static int
274 apecs_read_config(struct pci_bus *bus, unsigned int devfn, int where,
275 		  int size, u32 *value)
276 {
277 	unsigned long addr, pci_addr;
278 	unsigned char type1;
279 	long mask;
280 	int shift;
281 
282 	if (mk_conf_addr(bus, devfn, where, &pci_addr, &type1))
283 		return PCIBIOS_DEVICE_NOT_FOUND;
284 
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;
290 }
291 
292 static int
293 apecs_write_config(struct pci_bus *bus, unsigned int devfn, int where,
294 		   int size, u32 value)
295 {
296 	unsigned long addr, pci_addr;
297 	unsigned char type1;
298 	long mask;
299 
300 	if (mk_conf_addr(bus, devfn, where, &pci_addr, &type1))
301 		return PCIBIOS_DEVICE_NOT_FOUND;
302 
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;
307 }
308 
309 struct pci_ops apecs_pci_ops =
310 {
311 	.read =		apecs_read_config,
312 	.write =	apecs_write_config,
313 };
314 
315 void
316 apecs_pci_tbi(struct pci_controller *hose, dma_addr_t start, dma_addr_t end)
317 {
318 	wmb();
319 	*(vip)APECS_IOC_TBIA = 0;
320 	mb();
321 }
322 
323 void __init
324 apecs_init_arch(void)
325 {
326 	struct pci_controller *hose;
327 
328 	/*
329 	 * Create our single hose.
330 	 */
331 
332 	pci_isa_hose = hose = alloc_pci_controller();
333 	hose->io_space = &ioport_resource;
334 	hose->mem_space = &iomem_resource;
335 	hose->index = 0;
336 
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;
341 
342 	/*
343 	 * Set up the PCI to main memory translation windows.
344 	 *
345 	 * Window 1 is direct access 1GB at 1GB
346 	 * Window 2 is scatter-gather 8MB at 8MB (for isa)
347 	 */
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;
352 
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;
356 
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;
360 
361 	apecs_pci_tbi(hose, 0, -1);
362 
363 	/*
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...
368 	 */
369 	*(vuip)APECS_IOC_HAXR2 = 0;
370 	mb();
371 }
372 
373 void
374 apecs_pci_clr_err(void)
375 {
376 	unsigned int jd;
377 
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;
384 	}
385 	*(vuip)APECS_IOC_TBIA = (unsigned int)APECS_IOC_TBIA;
386 	mb();
387 	*(vuip)APECS_IOC_TBIA;
388 }
389 
390 void
391 apecs_machine_check(unsigned long vector, unsigned long la_ptr)
392 {
393 	struct el_common *mchk_header;
394 	struct el_apecs_procdata *mchk_procdata;
395 	struct el_apecs_sysdata_mcheck *mchk_sysdata;
396 
397 	mchk_header = (struct el_common *)la_ptr;
398 
399 	mchk_procdata = (struct el_apecs_procdata *)
400 		(la_ptr + mchk_header->proc_offset
401 		 - sizeof(mchk_procdata->paltemp));
402 
403 	mchk_sysdata = (struct el_apecs_sysdata_mcheck *)
404 		(la_ptr + mchk_header->sys_offset);
405 
406 
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();
414 
415 	process_mcheck_info(vector, la_ptr, "APECS",
416 			    (mcheck_expected(0)
417 			     && (mchk_sysdata->epic_dcsr & 0x0c00UL)));
418 }
419