xref: /openbmc/linux/drivers/char/agp/parisc-agp.c (revision 6db6b729)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HP Quicksilver AGP GART routines
4  *
5  * Copyright (c) 2006, Kyle McMartin <kyle@parisc-linux.org>
6  *
7  * Based on drivers/char/agpgart/hp-agp.c which is
8  * (c) Copyright 2002, 2003 Hewlett-Packard Development Company, L.P.
9  *	Bjorn Helgaas <bjorn.helgaas@hp.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/pci.h>
14 #include <linux/init.h>
15 #include <linux/klist.h>
16 #include <linux/agp_backend.h>
17 #include <linux/log2.h>
18 #include <linux/slab.h>
19 
20 #include <asm/parisc-device.h>
21 #include <asm/ropes.h>
22 
23 #include "agp.h"
24 
25 #define DRVNAME	"quicksilver"
26 #define DRVPFX	DRVNAME ": "
27 
28 #define AGP8X_MODE_BIT		3
29 #define AGP8X_MODE		(1 << AGP8X_MODE_BIT)
30 
31 static unsigned long
32 parisc_agp_mask_memory(struct agp_bridge_data *bridge, dma_addr_t addr,
33 		       int type);
34 
35 static struct _parisc_agp_info {
36 	void __iomem *ioc_regs;
37 	void __iomem *lba_regs;
38 
39 	int lba_cap_offset;
40 
41 	u64 *gatt;
42 	u64 gatt_entries;
43 
44 	u64 gart_base;
45 	u64 gart_size;
46 
47 	int io_page_size;
48 	int io_pages_per_kpage;
49 } parisc_agp_info;
50 
51 static struct gatt_mask parisc_agp_masks[] =
52 {
53         {
54 		.mask = SBA_PDIR_VALID_BIT,
55 		.type = 0
56 	}
57 };
58 
59 static struct aper_size_info_fixed parisc_agp_sizes[] =
60 {
61         {0, 0, 0},              /* filled in by parisc_agp_fetch_size() */
62 };
63 
64 static int
65 parisc_agp_fetch_size(void)
66 {
67 	int size;
68 
69 	size = parisc_agp_info.gart_size / MB(1);
70 	parisc_agp_sizes[0].size = size;
71 	agp_bridge->current_size = (void *) &parisc_agp_sizes[0];
72 
73 	return size;
74 }
75 
76 static int
77 parisc_agp_configure(void)
78 {
79 	struct _parisc_agp_info *info = &parisc_agp_info;
80 
81 	agp_bridge->gart_bus_addr = info->gart_base;
82 	agp_bridge->capndx = info->lba_cap_offset;
83 	agp_bridge->mode = readl(info->lba_regs+info->lba_cap_offset+PCI_AGP_STATUS);
84 
85 	return 0;
86 }
87 
88 static void
89 parisc_agp_tlbflush(struct agp_memory *mem)
90 {
91 	struct _parisc_agp_info *info = &parisc_agp_info;
92 
93 	/* force fdc ops to be visible to IOMMU */
94 	asm_io_sync();
95 
96 	writeq(info->gart_base | ilog2(info->gart_size), info->ioc_regs+IOC_PCOM);
97 	readq(info->ioc_regs+IOC_PCOM);	/* flush */
98 }
99 
100 static int
101 parisc_agp_create_gatt_table(struct agp_bridge_data *bridge)
102 {
103 	struct _parisc_agp_info *info = &parisc_agp_info;
104 	int i;
105 
106 	for (i = 0; i < info->gatt_entries; i++) {
107 		info->gatt[i] = (unsigned long)agp_bridge->scratch_page;
108 	}
109 
110 	return 0;
111 }
112 
113 static int
114 parisc_agp_free_gatt_table(struct agp_bridge_data *bridge)
115 {
116 	struct _parisc_agp_info *info = &parisc_agp_info;
117 
118 	info->gatt[0] = SBA_AGPGART_COOKIE;
119 
120 	return 0;
121 }
122 
123 static int
124 parisc_agp_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
125 {
126 	struct _parisc_agp_info *info = &parisc_agp_info;
127 	int i, k;
128 	off_t j, io_pg_start;
129 	int io_pg_count;
130 
131 	if (type != mem->type ||
132 		agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type)) {
133 		return -EINVAL;
134 	}
135 
136 	io_pg_start = info->io_pages_per_kpage * pg_start;
137 	io_pg_count = info->io_pages_per_kpage * mem->page_count;
138 	if ((io_pg_start + io_pg_count) > info->gatt_entries) {
139 		return -EINVAL;
140 	}
141 
142 	j = io_pg_start;
143 	while (j < (io_pg_start + io_pg_count)) {
144 		if (info->gatt[j])
145 			return -EBUSY;
146 		j++;
147 	}
148 
149 	if (!mem->is_flushed) {
150 		global_cache_flush();
151 		mem->is_flushed = true;
152 	}
153 
154 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
155 		unsigned long paddr;
156 
157 		paddr = page_to_phys(mem->pages[i]);
158 		for (k = 0;
159 		     k < info->io_pages_per_kpage;
160 		     k++, j++, paddr += info->io_page_size) {
161 			info->gatt[j] =
162 				parisc_agp_mask_memory(agp_bridge,
163 					paddr, type);
164 			asm_io_fdc(&info->gatt[j]);
165 		}
166 	}
167 
168 	agp_bridge->driver->tlb_flush(mem);
169 
170 	return 0;
171 }
172 
173 static int
174 parisc_agp_remove_memory(struct agp_memory *mem, off_t pg_start, int type)
175 {
176 	struct _parisc_agp_info *info = &parisc_agp_info;
177 	int i, io_pg_start, io_pg_count;
178 
179 	if (type != mem->type ||
180 		agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type)) {
181 		return -EINVAL;
182 	}
183 
184 	io_pg_start = info->io_pages_per_kpage * pg_start;
185 	io_pg_count = info->io_pages_per_kpage * mem->page_count;
186 	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
187 		info->gatt[i] = agp_bridge->scratch_page;
188 	}
189 
190 	agp_bridge->driver->tlb_flush(mem);
191 	return 0;
192 }
193 
194 static unsigned long
195 parisc_agp_mask_memory(struct agp_bridge_data *bridge, dma_addr_t addr,
196 		       int type)
197 {
198 	unsigned ci;			/* coherent index */
199 	dma_addr_t pa;
200 
201 	pa = addr & IOVP_MASK;
202 	asm("lci 0(%1), %0" : "=r" (ci) : "r" (phys_to_virt(pa)));
203 
204 	pa |= (ci >> PAGE_SHIFT) & 0xff;/* move CI (8 bits) into lowest byte */
205 	pa |= SBA_PDIR_VALID_BIT;	/* set "valid" bit */
206 
207 	return cpu_to_le64(pa);
208 }
209 
210 static void
211 parisc_agp_enable(struct agp_bridge_data *bridge, u32 mode)
212 {
213 	struct _parisc_agp_info *info = &parisc_agp_info;
214 	u32 command;
215 
216 	command = readl(info->lba_regs + info->lba_cap_offset + PCI_AGP_STATUS);
217 
218 	command = agp_collect_device_status(bridge, mode, command);
219 	command |= 0x00000100;
220 
221 	writel(command, info->lba_regs + info->lba_cap_offset + PCI_AGP_COMMAND);
222 
223 	agp_device_command(command, (mode & AGP8X_MODE) != 0);
224 }
225 
226 static const struct agp_bridge_driver parisc_agp_driver = {
227 	.owner			= THIS_MODULE,
228 	.size_type		= FIXED_APER_SIZE,
229 	.configure		= parisc_agp_configure,
230 	.fetch_size		= parisc_agp_fetch_size,
231 	.tlb_flush		= parisc_agp_tlbflush,
232 	.mask_memory		= parisc_agp_mask_memory,
233 	.masks			= parisc_agp_masks,
234 	.agp_enable		= parisc_agp_enable,
235 	.cache_flush		= global_cache_flush,
236 	.create_gatt_table	= parisc_agp_create_gatt_table,
237 	.free_gatt_table	= parisc_agp_free_gatt_table,
238 	.insert_memory		= parisc_agp_insert_memory,
239 	.remove_memory		= parisc_agp_remove_memory,
240 	.alloc_by_type		= agp_generic_alloc_by_type,
241 	.free_by_type		= agp_generic_free_by_type,
242 	.agp_alloc_page		= agp_generic_alloc_page,
243 	.agp_alloc_pages	= agp_generic_alloc_pages,
244 	.agp_destroy_page	= agp_generic_destroy_page,
245 	.agp_destroy_pages	= agp_generic_destroy_pages,
246 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
247 	.cant_use_aperture	= true,
248 };
249 
250 static int __init
251 agp_ioc_init(void __iomem *ioc_regs)
252 {
253 	struct _parisc_agp_info *info = &parisc_agp_info;
254         u64 iova_base, *io_pdir, io_tlb_ps;
255         int io_tlb_shift;
256 
257         printk(KERN_INFO DRVPFX "IO PDIR shared with sba_iommu\n");
258 
259         info->ioc_regs = ioc_regs;
260 
261         io_tlb_ps = readq(info->ioc_regs+IOC_TCNFG);
262         switch (io_tlb_ps) {
263         case 0: io_tlb_shift = 12; break;
264         case 1: io_tlb_shift = 13; break;
265         case 2: io_tlb_shift = 14; break;
266         case 3: io_tlb_shift = 16; break;
267         default:
268                 printk(KERN_ERR DRVPFX "Invalid IOTLB page size "
269                        "configuration 0x%llx\n", io_tlb_ps);
270                 info->gatt = NULL;
271                 info->gatt_entries = 0;
272                 return -ENODEV;
273         }
274         info->io_page_size = 1 << io_tlb_shift;
275         info->io_pages_per_kpage = PAGE_SIZE / info->io_page_size;
276 
277         iova_base = readq(info->ioc_regs+IOC_IBASE) & ~0x1;
278         info->gart_base = iova_base + PLUTO_IOVA_SIZE - PLUTO_GART_SIZE;
279 
280         info->gart_size = PLUTO_GART_SIZE;
281         info->gatt_entries = info->gart_size / info->io_page_size;
282 
283         io_pdir = phys_to_virt(readq(info->ioc_regs+IOC_PDIR_BASE));
284         info->gatt = &io_pdir[(PLUTO_IOVA_SIZE/2) >> PAGE_SHIFT];
285 
286         if (info->gatt[0] != SBA_AGPGART_COOKIE) {
287                 info->gatt = NULL;
288                 info->gatt_entries = 0;
289                 printk(KERN_ERR DRVPFX "No reserved IO PDIR entry found; "
290                        "GART disabled\n");
291                 return -ENODEV;
292         }
293 
294         return 0;
295 }
296 
297 static int __init
298 lba_find_capability(int cap)
299 {
300 	struct _parisc_agp_info *info = &parisc_agp_info;
301         u16 status;
302         u8 pos, id;
303         int ttl = 48;
304 
305         status = readw(info->lba_regs + PCI_STATUS);
306         if (!(status & PCI_STATUS_CAP_LIST))
307                 return 0;
308         pos = readb(info->lba_regs + PCI_CAPABILITY_LIST);
309         while (ttl-- && pos >= 0x40) {
310                 pos &= ~3;
311                 id = readb(info->lba_regs + pos + PCI_CAP_LIST_ID);
312                 if (id == 0xff)
313                         break;
314                 if (id == cap)
315                         return pos;
316                 pos = readb(info->lba_regs + pos + PCI_CAP_LIST_NEXT);
317         }
318         return 0;
319 }
320 
321 static int __init
322 agp_lba_init(void __iomem *lba_hpa)
323 {
324 	struct _parisc_agp_info *info = &parisc_agp_info;
325         int cap;
326 
327 	info->lba_regs = lba_hpa;
328         info->lba_cap_offset = lba_find_capability(PCI_CAP_ID_AGP);
329 
330         cap = readl(lba_hpa + info->lba_cap_offset) & 0xff;
331         if (cap != PCI_CAP_ID_AGP) {
332                 printk(KERN_ERR DRVPFX "Invalid capability ID 0x%02x at 0x%x\n",
333                        cap, info->lba_cap_offset);
334                 return -ENODEV;
335         }
336 
337         return 0;
338 }
339 
340 static int __init
341 parisc_agp_setup(void __iomem *ioc_hpa, void __iomem *lba_hpa)
342 {
343 	struct pci_dev *fake_bridge_dev = NULL;
344 	struct agp_bridge_data *bridge;
345 	int error = 0;
346 
347 	fake_bridge_dev = pci_alloc_dev(NULL);
348 	if (!fake_bridge_dev) {
349 		error = -ENOMEM;
350 		goto fail;
351 	}
352 
353 	error = agp_ioc_init(ioc_hpa);
354 	if (error)
355 		goto fail;
356 
357 	error = agp_lba_init(lba_hpa);
358 	if (error)
359 		goto fail;
360 
361 	bridge = agp_alloc_bridge();
362 	if (!bridge) {
363 		error = -ENOMEM;
364 		goto fail;
365 	}
366 	bridge->driver = &parisc_agp_driver;
367 
368 	fake_bridge_dev->vendor = PCI_VENDOR_ID_HP;
369 	fake_bridge_dev->device = PCI_DEVICE_ID_HP_PCIX_LBA;
370 	bridge->dev = fake_bridge_dev;
371 
372 	error = agp_add_bridge(bridge);
373 	if (error)
374 		goto fail;
375 	return 0;
376 
377 fail:
378 	kfree(fake_bridge_dev);
379 	return error;
380 }
381 
382 static int __init
383 find_quicksilver(struct device *dev, void *data)
384 {
385 	struct parisc_device **lba = data;
386 	struct parisc_device *padev = to_parisc_device(dev);
387 
388 	if (IS_QUICKSILVER(padev))
389 		*lba = padev;
390 
391 	return 0;
392 }
393 
394 static int __init
395 parisc_agp_init(void)
396 {
397 	int err = -1;
398 	struct parisc_device *sba = NULL, *lba = NULL;
399 	struct lba_device *lbadev = NULL;
400 
401 	if (!sba_list)
402 		goto out;
403 
404 	/* Find our parent Pluto */
405 	sba = sba_list->dev;
406 	if (!IS_PLUTO(sba)) {
407 		printk(KERN_INFO DRVPFX "No Pluto found, so no AGPGART for you.\n");
408 		goto out;
409 	}
410 
411 	/* Now search our Pluto for our precious AGP device... */
412 	device_for_each_child(&sba->dev, &lba, find_quicksilver);
413 
414 	if (!lba) {
415 		printk(KERN_INFO DRVPFX "No AGP devices found.\n");
416 		goto out;
417 	}
418 
419 	lbadev = parisc_get_drvdata(lba);
420 
421 	/* w00t, let's go find our cookies... */
422 	parisc_agp_setup(sba_list->ioc[0].ioc_hpa, lbadev->hba.base_addr);
423 
424 	return 0;
425 
426 out:
427 	return err;
428 }
429 
430 module_init(parisc_agp_init);
431 
432 MODULE_AUTHOR("Kyle McMartin <kyle@parisc-linux.org>");
433 MODULE_LICENSE("GPL");
434