xref: /openbmc/linux/drivers/char/agp/parisc-agp.c (revision 9a29f5fc)
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 	writeq(info->gart_base | ilog2(info->gart_size), info->ioc_regs+IOC_PCOM);
94 	readq(info->ioc_regs+IOC_PCOM);	/* flush */
95 }
96 
97 static int
98 parisc_agp_create_gatt_table(struct agp_bridge_data *bridge)
99 {
100 	struct _parisc_agp_info *info = &parisc_agp_info;
101 	int i;
102 
103 	for (i = 0; i < info->gatt_entries; i++) {
104 		info->gatt[i] = (unsigned long)agp_bridge->scratch_page;
105 	}
106 
107 	return 0;
108 }
109 
110 static int
111 parisc_agp_free_gatt_table(struct agp_bridge_data *bridge)
112 {
113 	struct _parisc_agp_info *info = &parisc_agp_info;
114 
115 	info->gatt[0] = SBA_AGPGART_COOKIE;
116 
117 	return 0;
118 }
119 
120 static int
121 parisc_agp_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
122 {
123 	struct _parisc_agp_info *info = &parisc_agp_info;
124 	int i, k;
125 	off_t j, io_pg_start;
126 	int io_pg_count;
127 
128 	if (type != mem->type ||
129 		agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type)) {
130 		return -EINVAL;
131 	}
132 
133 	io_pg_start = info->io_pages_per_kpage * pg_start;
134 	io_pg_count = info->io_pages_per_kpage * mem->page_count;
135 	if ((io_pg_start + io_pg_count) > info->gatt_entries) {
136 		return -EINVAL;
137 	}
138 
139 	j = io_pg_start;
140 	while (j < (io_pg_start + io_pg_count)) {
141 		if (info->gatt[j])
142 			return -EBUSY;
143 		j++;
144 	}
145 
146 	if (!mem->is_flushed) {
147 		global_cache_flush();
148 		mem->is_flushed = true;
149 	}
150 
151 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
152 		unsigned long paddr;
153 
154 		paddr = page_to_phys(mem->pages[i]);
155 		for (k = 0;
156 		     k < info->io_pages_per_kpage;
157 		     k++, j++, paddr += info->io_page_size) {
158 			info->gatt[j] =
159 				parisc_agp_mask_memory(agp_bridge,
160 					paddr, type);
161 		}
162 	}
163 
164 	agp_bridge->driver->tlb_flush(mem);
165 
166 	return 0;
167 }
168 
169 static int
170 parisc_agp_remove_memory(struct agp_memory *mem, off_t pg_start, int type)
171 {
172 	struct _parisc_agp_info *info = &parisc_agp_info;
173 	int i, io_pg_start, io_pg_count;
174 
175 	if (type != mem->type ||
176 		agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type)) {
177 		return -EINVAL;
178 	}
179 
180 	io_pg_start = info->io_pages_per_kpage * pg_start;
181 	io_pg_count = info->io_pages_per_kpage * mem->page_count;
182 	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
183 		info->gatt[i] = agp_bridge->scratch_page;
184 	}
185 
186 	agp_bridge->driver->tlb_flush(mem);
187 	return 0;
188 }
189 
190 static unsigned long
191 parisc_agp_mask_memory(struct agp_bridge_data *bridge, dma_addr_t addr,
192 		       int type)
193 {
194 	return SBA_PDIR_VALID_BIT | addr;
195 }
196 
197 static void
198 parisc_agp_enable(struct agp_bridge_data *bridge, u32 mode)
199 {
200 	struct _parisc_agp_info *info = &parisc_agp_info;
201 	u32 command;
202 
203 	command = readl(info->lba_regs + info->lba_cap_offset + PCI_AGP_STATUS);
204 
205 	command = agp_collect_device_status(bridge, mode, command);
206 	command |= 0x00000100;
207 
208 	writel(command, info->lba_regs + info->lba_cap_offset + PCI_AGP_COMMAND);
209 
210 	agp_device_command(command, (mode & AGP8X_MODE) != 0);
211 }
212 
213 static const struct agp_bridge_driver parisc_agp_driver = {
214 	.owner			= THIS_MODULE,
215 	.size_type		= FIXED_APER_SIZE,
216 	.configure		= parisc_agp_configure,
217 	.fetch_size		= parisc_agp_fetch_size,
218 	.tlb_flush		= parisc_agp_tlbflush,
219 	.mask_memory		= parisc_agp_mask_memory,
220 	.masks			= parisc_agp_masks,
221 	.agp_enable		= parisc_agp_enable,
222 	.cache_flush		= global_cache_flush,
223 	.create_gatt_table	= parisc_agp_create_gatt_table,
224 	.free_gatt_table	= parisc_agp_free_gatt_table,
225 	.insert_memory		= parisc_agp_insert_memory,
226 	.remove_memory		= parisc_agp_remove_memory,
227 	.alloc_by_type		= agp_generic_alloc_by_type,
228 	.free_by_type		= agp_generic_free_by_type,
229 	.agp_alloc_page		= agp_generic_alloc_page,
230 	.agp_alloc_pages	= agp_generic_alloc_pages,
231 	.agp_destroy_page	= agp_generic_destroy_page,
232 	.agp_destroy_pages	= agp_generic_destroy_pages,
233 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
234 	.cant_use_aperture	= true,
235 };
236 
237 static int __init
238 agp_ioc_init(void __iomem *ioc_regs)
239 {
240 	struct _parisc_agp_info *info = &parisc_agp_info;
241         u64 iova_base, *io_pdir, io_tlb_ps;
242         int io_tlb_shift;
243 
244         printk(KERN_INFO DRVPFX "IO PDIR shared with sba_iommu\n");
245 
246         info->ioc_regs = ioc_regs;
247 
248         io_tlb_ps = readq(info->ioc_regs+IOC_TCNFG);
249         switch (io_tlb_ps) {
250         case 0: io_tlb_shift = 12; break;
251         case 1: io_tlb_shift = 13; break;
252         case 2: io_tlb_shift = 14; break;
253         case 3: io_tlb_shift = 16; break;
254         default:
255                 printk(KERN_ERR DRVPFX "Invalid IOTLB page size "
256                        "configuration 0x%llx\n", io_tlb_ps);
257                 info->gatt = NULL;
258                 info->gatt_entries = 0;
259                 return -ENODEV;
260         }
261         info->io_page_size = 1 << io_tlb_shift;
262         info->io_pages_per_kpage = PAGE_SIZE / info->io_page_size;
263 
264         iova_base = readq(info->ioc_regs+IOC_IBASE) & ~0x1;
265         info->gart_base = iova_base + PLUTO_IOVA_SIZE - PLUTO_GART_SIZE;
266 
267         info->gart_size = PLUTO_GART_SIZE;
268         info->gatt_entries = info->gart_size / info->io_page_size;
269 
270         io_pdir = phys_to_virt(readq(info->ioc_regs+IOC_PDIR_BASE));
271         info->gatt = &io_pdir[(PLUTO_IOVA_SIZE/2) >> PAGE_SHIFT];
272 
273         if (info->gatt[0] != SBA_AGPGART_COOKIE) {
274                 info->gatt = NULL;
275                 info->gatt_entries = 0;
276                 printk(KERN_ERR DRVPFX "No reserved IO PDIR entry found; "
277                        "GART disabled\n");
278                 return -ENODEV;
279         }
280 
281         return 0;
282 }
283 
284 static int __init
285 lba_find_capability(int cap)
286 {
287 	struct _parisc_agp_info *info = &parisc_agp_info;
288         u16 status;
289         u8 pos, id;
290         int ttl = 48;
291 
292         status = readw(info->lba_regs + PCI_STATUS);
293         if (!(status & PCI_STATUS_CAP_LIST))
294                 return 0;
295         pos = readb(info->lba_regs + PCI_CAPABILITY_LIST);
296         while (ttl-- && pos >= 0x40) {
297                 pos &= ~3;
298                 id = readb(info->lba_regs + pos + PCI_CAP_LIST_ID);
299                 if (id == 0xff)
300                         break;
301                 if (id == cap)
302                         return pos;
303                 pos = readb(info->lba_regs + pos + PCI_CAP_LIST_NEXT);
304         }
305         return 0;
306 }
307 
308 static int __init
309 agp_lba_init(void __iomem *lba_hpa)
310 {
311 	struct _parisc_agp_info *info = &parisc_agp_info;
312         int cap;
313 
314 	info->lba_regs = lba_hpa;
315         info->lba_cap_offset = lba_find_capability(PCI_CAP_ID_AGP);
316 
317         cap = readl(lba_hpa + info->lba_cap_offset) & 0xff;
318         if (cap != PCI_CAP_ID_AGP) {
319                 printk(KERN_ERR DRVPFX "Invalid capability ID 0x%02x at 0x%x\n",
320                        cap, info->lba_cap_offset);
321                 return -ENODEV;
322         }
323 
324         return 0;
325 }
326 
327 static int __init
328 parisc_agp_setup(void __iomem *ioc_hpa, void __iomem *lba_hpa)
329 {
330 	struct pci_dev *fake_bridge_dev = NULL;
331 	struct agp_bridge_data *bridge;
332 	int error = 0;
333 
334 	fake_bridge_dev = pci_alloc_dev(NULL);
335 	if (!fake_bridge_dev) {
336 		error = -ENOMEM;
337 		goto fail;
338 	}
339 
340 	error = agp_ioc_init(ioc_hpa);
341 	if (error)
342 		goto fail;
343 
344 	error = agp_lba_init(lba_hpa);
345 	if (error)
346 		goto fail;
347 
348 	bridge = agp_alloc_bridge();
349 	if (!bridge) {
350 		error = -ENOMEM;
351 		goto fail;
352 	}
353 	bridge->driver = &parisc_agp_driver;
354 
355 	fake_bridge_dev->vendor = PCI_VENDOR_ID_HP;
356 	fake_bridge_dev->device = PCI_DEVICE_ID_HP_PCIX_LBA;
357 	bridge->dev = fake_bridge_dev;
358 
359 	error = agp_add_bridge(bridge);
360 	if (error)
361 		goto fail;
362 	return 0;
363 
364 fail:
365 	kfree(fake_bridge_dev);
366 	return error;
367 }
368 
369 static int __init
370 find_quicksilver(struct device *dev, void *data)
371 {
372 	struct parisc_device **lba = data;
373 	struct parisc_device *padev = to_parisc_device(dev);
374 
375 	if (IS_QUICKSILVER(padev))
376 		*lba = padev;
377 
378 	return 0;
379 }
380 
381 static int __init
382 parisc_agp_init(void)
383 {
384 	extern struct sba_device *sba_list;
385 
386 	int err = -1;
387 	struct parisc_device *sba = NULL, *lba = NULL;
388 	struct lba_device *lbadev = NULL;
389 
390 	if (!sba_list)
391 		goto out;
392 
393 	/* Find our parent Pluto */
394 	sba = sba_list->dev;
395 	if (!IS_PLUTO(sba)) {
396 		printk(KERN_INFO DRVPFX "No Pluto found, so no AGPGART for you.\n");
397 		goto out;
398 	}
399 
400 	/* Now search our Pluto for our precious AGP device... */
401 	device_for_each_child(&sba->dev, &lba, find_quicksilver);
402 
403 	if (!lba) {
404 		printk(KERN_INFO DRVPFX "No AGP devices found.\n");
405 		goto out;
406 	}
407 
408 	lbadev = parisc_get_drvdata(lba);
409 
410 	/* w00t, let's go find our cookies... */
411 	parisc_agp_setup(sba_list->ioc[0].ioc_hpa, lbadev->hba.base_addr);
412 
413 	return 0;
414 
415 out:
416 	return err;
417 }
418 
419 module_init(parisc_agp_init);
420 
421 MODULE_AUTHOR("Kyle McMartin <kyle@parisc-linux.org>");
422 MODULE_LICENSE("GPL");
423