1 /*
2  *	linux/arch/alpha/kernel/core_irongate.c
3  *
4  * Based on code written by David A. Rusling (david.rusling@reo.mts.dec.com).
5  *
6  *	Copyright (C) 1999 Alpha Processor, Inc.,
7  *		(David Daniel, Stig Telfer, Soohoon Lee)
8  *
9  * Code common to all IRONGATE core logic chips.
10  */
11 
12 #define __EXTERN_INLINE inline
13 #include <asm/io.h>
14 #include <asm/core_irongate.h>
15 #undef __EXTERN_INLINE
16 
17 #include <linux/types.h>
18 #include <linux/pci.h>
19 #include <linux/sched.h>
20 #include <linux/init.h>
21 #include <linux/initrd.h>
22 #include <linux/bootmem.h>
23 
24 #include <asm/ptrace.h>
25 #include <asm/pci.h>
26 #include <asm/cacheflush.h>
27 #include <asm/tlbflush.h>
28 
29 #include "proto.h"
30 #include "pci_impl.h"
31 
32 /*
33  * BIOS32-style PCI interface:
34  */
35 
36 #define DEBUG_CONFIG 0
37 
38 #if DEBUG_CONFIG
39 # define DBG_CFG(args)	printk args
40 #else
41 # define DBG_CFG(args)
42 #endif
43 
44 igcsr32 *IronECC;
45 
46 /*
47  * Given a bus, device, and function number, compute resulting
48  * configuration space address accordingly.  It is therefore not safe
49  * to have concurrent invocations to configuration space access
50  * routines, but there really shouldn't be any need for this.
51  *
52  *	addr[31:24]		reserved
53  *	addr[23:16]		bus number (8 bits = 128 possible buses)
54  *	addr[15:11]		Device number (5 bits)
55  *	addr[10: 8]		function number
56  *	addr[ 7: 2]		register number
57  *
58  * For IRONGATE:
59  *    if (bus = addr[23:16]) == 0
60  *    then
61  *	  type 0 config cycle:
62  *	      addr_on_pci[31:11] = id selection for device = addr[15:11]
63  *	      addr_on_pci[10: 2] = addr[10: 2] ???
64  *	      addr_on_pci[ 1: 0] = 00
65  *    else
66  *	  type 1 config cycle (pass on with no decoding):
67  *	      addr_on_pci[31:24] = 0
68  *	      addr_on_pci[23: 2] = addr[23: 2]
69  *	      addr_on_pci[ 1: 0] = 01
70  *    fi
71  *
72  * Notes:
73  *	The function number selects which function of a multi-function device
74  *	(e.g., SCSI and Ethernet).
75  *
76  *	The register selects a DWORD (32 bit) register offset.	Hence it
77  *	doesn't get shifted by 2 bits as we want to "drop" the bottom two
78  *	bits.
79  */
80 
81 static int
82 mk_conf_addr(struct pci_bus *pbus, unsigned int device_fn, int where,
83 	     unsigned long *pci_addr, unsigned char *type1)
84 {
85 	unsigned long addr;
86 	u8 bus = pbus->number;
87 
88 	DBG_CFG(("mk_conf_addr(bus=%d ,device_fn=0x%x, where=0x%x, "
89 		 "pci_addr=0x%p, type1=0x%p)\n",
90 		 bus, device_fn, where, pci_addr, type1));
91 
92 	*type1 = (bus != 0);
93 
94 	addr = (bus << 16) | (device_fn << 8) | where;
95 	addr |= IRONGATE_CONF;
96 
97 	*pci_addr = addr;
98 	DBG_CFG(("mk_conf_addr: returning pci_addr 0x%lx\n", addr));
99 	return 0;
100 }
101 
102 static int
103 irongate_read_config(struct pci_bus *bus, unsigned int devfn, int where,
104 		     int size, u32 *value)
105 {
106 	unsigned long addr;
107 	unsigned char type1;
108 
109 	if (mk_conf_addr(bus, devfn, where, &addr, &type1))
110 		return PCIBIOS_DEVICE_NOT_FOUND;
111 
112 	switch (size) {
113 	case 1:
114 		*value = __kernel_ldbu(*(vucp)addr);
115 		break;
116 	case 2:
117 		*value = __kernel_ldwu(*(vusp)addr);
118 		break;
119 	case 4:
120 		*value = *(vuip)addr;
121 		break;
122 	}
123 
124 	return PCIBIOS_SUCCESSFUL;
125 }
126 
127 static int
128 irongate_write_config(struct pci_bus *bus, unsigned int devfn, int where,
129 		      int size, u32 value)
130 {
131 	unsigned long addr;
132 	unsigned char type1;
133 
134 	if (mk_conf_addr(bus, devfn, where, &addr, &type1))
135 		return PCIBIOS_DEVICE_NOT_FOUND;
136 
137 	switch (size) {
138 	case 1:
139 		__kernel_stb(value, *(vucp)addr);
140 		mb();
141 		__kernel_ldbu(*(vucp)addr);
142 		break;
143 	case 2:
144 		__kernel_stw(value, *(vusp)addr);
145 		mb();
146 		__kernel_ldwu(*(vusp)addr);
147 		break;
148 	case 4:
149 		*(vuip)addr = value;
150 		mb();
151 		*(vuip)addr;
152 		break;
153 	}
154 
155 	return PCIBIOS_SUCCESSFUL;
156 }
157 
158 struct pci_ops irongate_pci_ops =
159 {
160 	.read =		irongate_read_config,
161 	.write =	irongate_write_config,
162 };
163 
164 int
165 irongate_pci_clr_err(void)
166 {
167 	unsigned int nmi_ctl=0;
168 	unsigned int IRONGATE_jd;
169 
170 again:
171 	IRONGATE_jd = IRONGATE0->stat_cmd;
172 	printk("Iron stat_cmd %x\n", IRONGATE_jd);
173 	IRONGATE0->stat_cmd = IRONGATE_jd; /* write again clears error bits */
174 	mb();
175 	IRONGATE_jd = IRONGATE0->stat_cmd;  /* re-read to force write */
176 
177 	IRONGATE_jd = *IronECC;
178 	printk("Iron ECC %x\n", IRONGATE_jd);
179 	*IronECC = IRONGATE_jd; /* write again clears error bits */
180 	mb();
181 	IRONGATE_jd = *IronECC;  /* re-read to force write */
182 
183 	/* Clear ALI NMI */
184         nmi_ctl = inb(0x61);
185         nmi_ctl |= 0x0c;
186         outb(nmi_ctl, 0x61);
187         nmi_ctl &= ~0x0c;
188         outb(nmi_ctl, 0x61);
189 
190 	IRONGATE_jd = *IronECC;
191 	if (IRONGATE_jd & 0x300) goto again;
192 
193 	return 0;
194 }
195 
196 #define IRONGATE_3GB 0xc0000000UL
197 
198 /* On Albacore (aka UP1500) with 4Gb of RAM we have to reserve some
199    memory for PCI. At this point we just reserve memory above 3Gb. Most
200    of this memory will be freed after PCI setup is done. */
201 static void __init
202 albacore_init_arch(void)
203 {
204 	unsigned long memtop = max_low_pfn << PAGE_SHIFT;
205 	unsigned long pci_mem = (memtop + 0x1000000UL) & ~0xffffffUL;
206 	struct percpu_struct *cpu;
207 	int pal_rev, pal_var;
208 
209 	cpu = (struct percpu_struct*)((char*)hwrpb + hwrpb->processor_offset);
210 	pal_rev = cpu->pal_revision & 0xffff;
211 	pal_var = (cpu->pal_revision >> 16) & 0xff;
212 
213 	/* Consoles earlier than A5.6-18 (OSF PALcode v1.62-2) set up
214 	   the CPU incorrectly (leave speculative stores enabled),
215 	   which causes memory corruption under certain conditions.
216 	   Issue a warning for such consoles. */
217 	if (alpha_using_srm &&
218 	    (pal_rev < 0x13e ||	(pal_rev == 0x13e && pal_var < 2)))
219 		printk(KERN_WARNING "WARNING! Upgrade to SRM A5.6-19 "
220 				    "or later\n");
221 
222 	if (pci_mem > IRONGATE_3GB)
223 		pci_mem = IRONGATE_3GB;
224 	IRONGATE0->pci_mem = pci_mem;
225 	alpha_mv.min_mem_address = pci_mem;
226 	if (memtop > pci_mem) {
227 #ifdef CONFIG_BLK_DEV_INITRD
228 		extern unsigned long initrd_start, initrd_end;
229 		extern void *move_initrd(unsigned long);
230 
231 		/* Move the initrd out of the way. */
232 		if (initrd_end && __pa(initrd_end) > pci_mem) {
233 			unsigned long size;
234 
235 			size = initrd_end - initrd_start;
236 			free_bootmem_node(NODE_DATA(0), __pa(initrd_start),
237 					  PAGE_ALIGN(size));
238 			if (!move_initrd(pci_mem))
239 				printk("irongate_init_arch: initrd too big "
240 				       "(%ldK)\ndisabling initrd\n",
241 				       size / 1024);
242 		}
243 #endif
244 		reserve_bootmem_node(NODE_DATA(0), pci_mem, memtop - pci_mem);
245 		printk("irongate_init_arch: temporarily reserving "
246 			"region %08lx-%08lx for PCI\n", pci_mem, memtop - 1);
247 	}
248 }
249 
250 static void __init
251 irongate_setup_agp(void)
252 {
253 	/* Disable the GART window. AGPGART doesn't work due to yet
254 	   unresolved memory coherency issues... */
255 	IRONGATE0->agpva = IRONGATE0->agpva & ~0xf;
256 	alpha_agpgart_size = 0;
257 }
258 
259 void __init
260 irongate_init_arch(void)
261 {
262 	struct pci_controller *hose;
263 	int amd761 = (IRONGATE0->dev_vendor >> 16) > 0x7006;	/* Albacore? */
264 
265 	IronECC = amd761 ? &IRONGATE0->bacsr54_eccms761 : &IRONGATE0->dramms;
266 
267 	irongate_pci_clr_err();
268 
269 	if (amd761)
270 		albacore_init_arch();
271 
272 	irongate_setup_agp();
273 
274 	/*
275 	 * Create our single hose.
276 	 */
277 
278 	pci_isa_hose = hose = alloc_pci_controller();
279 	hose->io_space = &ioport_resource;
280 	hose->mem_space = &iomem_resource;
281 	hose->index = 0;
282 
283 	/* This is for userland consumption.  For some reason, the 40-bit
284 	   PIO bias that we use in the kernel through KSEG didn't work for
285 	   the page table based user mappings.  So make sure we get the
286 	   43-bit PIO bias.  */
287 	hose->sparse_mem_base = 0;
288 	hose->sparse_io_base = 0;
289 	hose->dense_mem_base
290 	  = (IRONGATE_MEM & 0xffffffffffUL) | 0x80000000000UL;
291 	hose->dense_io_base
292 	  = (IRONGATE_IO & 0xffffffffffUL) | 0x80000000000UL;
293 
294 	hose->sg_isa = hose->sg_pci = NULL;
295 	__direct_map_base = 0;
296 	__direct_map_size = 0xffffffff;
297 }
298 
299 /*
300  * IO map and AGP support
301  */
302 #include <linux/vmalloc.h>
303 #include <linux/agp_backend.h>
304 #include <linux/agpgart.h>
305 #include <asm/pgalloc.h>
306 
307 #define GET_PAGE_DIR_OFF(addr) (addr >> 22)
308 #define GET_PAGE_DIR_IDX(addr) (GET_PAGE_DIR_OFF(addr))
309 
310 #define GET_GATT_OFF(addr) ((addr & 0x003ff000) >> 12)
311 #define GET_GATT(addr) (gatt_pages[GET_PAGE_DIR_IDX(addr)])
312 
313 void __iomem *
314 irongate_ioremap(unsigned long addr, unsigned long size)
315 {
316 	struct vm_struct *area;
317 	unsigned long vaddr;
318 	unsigned long baddr, last;
319 	u32 *mmio_regs, *gatt_pages, *cur_gatt, pte;
320 	unsigned long gart_bus_addr;
321 
322 	if (!alpha_agpgart_size)
323 		return (void __iomem *)(addr + IRONGATE_MEM);
324 
325 	gart_bus_addr = (unsigned long)IRONGATE0->bar0 &
326 			PCI_BASE_ADDRESS_MEM_MASK;
327 
328 	/*
329 	 * Check for within the AGP aperture...
330 	 */
331 	do {
332 		/*
333 		 * Check the AGP area
334 		 */
335 		if (addr >= gart_bus_addr && addr + size - 1 <
336 		    gart_bus_addr + alpha_agpgart_size)
337 			break;
338 
339 		/*
340 		 * Not found - assume legacy ioremap
341 		 */
342 		return (void __iomem *)(addr + IRONGATE_MEM);
343 	} while(0);
344 
345 	mmio_regs = (u32 *)(((unsigned long)IRONGATE0->bar1 &
346 			PCI_BASE_ADDRESS_MEM_MASK) + IRONGATE_MEM);
347 
348 	gatt_pages = (u32 *)(phys_to_virt(mmio_regs[1])); /* FIXME */
349 
350 	/*
351 	 * Adjust the limits (mappings must be page aligned)
352 	 */
353 	if (addr & ~PAGE_MASK) {
354 		printk("AGP ioremap failed... addr not page aligned (0x%lx)\n",
355 		       addr);
356 		return (void __iomem *)(addr + IRONGATE_MEM);
357 	}
358 	last = addr + size - 1;
359 	size = PAGE_ALIGN(last) - addr;
360 
361 #if 0
362 	printk("irongate_ioremap(0x%lx, 0x%lx)\n", addr, size);
363 	printk("irongate_ioremap:  gart_bus_addr  0x%lx\n", gart_bus_addr);
364 	printk("irongate_ioremap:  gart_aper_size 0x%lx\n", gart_aper_size);
365 	printk("irongate_ioremap:  mmio_regs      %p\n", mmio_regs);
366 	printk("irongate_ioremap:  gatt_pages     %p\n", gatt_pages);
367 
368 	for(baddr = addr; baddr <= last; baddr += PAGE_SIZE)
369 	{
370 		cur_gatt = phys_to_virt(GET_GATT(baddr) & ~1);
371 		pte = cur_gatt[GET_GATT_OFF(baddr)] & ~1;
372 		printk("irongate_ioremap:  cur_gatt %p pte 0x%x\n",
373 		       cur_gatt, pte);
374 	}
375 #endif
376 
377 	/*
378 	 * Map it
379 	 */
380 	area = get_vm_area(size, VM_IOREMAP);
381 	if (!area) return NULL;
382 
383 	for(baddr = addr, vaddr = (unsigned long)area->addr;
384 	    baddr <= last;
385 	    baddr += PAGE_SIZE, vaddr += PAGE_SIZE)
386 	{
387 		cur_gatt = phys_to_virt(GET_GATT(baddr) & ~1);
388 		pte = cur_gatt[GET_GATT_OFF(baddr)] & ~1;
389 
390 		if (__alpha_remap_area_pages(vaddr,
391 					     pte, PAGE_SIZE, 0)) {
392 			printk("AGP ioremap: FAILED to map...\n");
393 			vfree(area->addr);
394 			return NULL;
395 		}
396 	}
397 
398 	flush_tlb_all();
399 
400 	vaddr = (unsigned long)area->addr + (addr & ~PAGE_MASK);
401 #if 0
402 	printk("irongate_ioremap(0x%lx, 0x%lx) returning 0x%lx\n",
403 	       addr, size, vaddr);
404 #endif
405 	return (void __iomem *)vaddr;
406 }
407 EXPORT_SYMBOL(irongate_ioremap);
408 
409 void
410 irongate_iounmap(volatile void __iomem *xaddr)
411 {
412 	unsigned long addr = (unsigned long) xaddr;
413 	if (((long)addr >> 41) == -2)
414 		return;	/* kseg map, nothing to do */
415 	if (addr)
416 		return vfree((void *)(PAGE_MASK & addr));
417 }
418 EXPORT_SYMBOL(irongate_iounmap);
419