Committer: Michael Beasley <mike@snafu.setup>
[mikesnafu-overlay.git] / arch / ia64 / sn / pci / pci_dma.c
blob18b94b792d5491bad4ccf3f650ce0feecfaed073
1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
6 * Copyright (C) 2000,2002-2005 Silicon Graphics, Inc. All rights reserved.
8 * Routines for PCI DMA mapping. See Documentation/DMA-API.txt for
9 * a description of how these routines should be used.
12 #include <linux/module.h>
13 #include <asm/dma.h>
14 #include <asm/sn/intr.h>
15 #include <asm/sn/pcibus_provider_defs.h>
16 #include <asm/sn/pcidev.h>
17 #include <asm/sn/sn_sal.h>
19 #define SG_ENT_VIRT_ADDRESS(sg) (sg_virt((sg)))
20 #define SG_ENT_PHYS_ADDRESS(SG) virt_to_phys(SG_ENT_VIRT_ADDRESS(SG))
22 /**
23 * sn_dma_supported - test a DMA mask
24 * @dev: device to test
25 * @mask: DMA mask to test
27 * Return whether the given PCI device DMA address mask can be supported
28 * properly. For example, if your device can only drive the low 24-bits
29 * during PCI bus mastering, then you would pass 0x00ffffff as the mask to
30 * this function. Of course, SN only supports devices that have 32 or more
31 * address bits when using the PMU.
33 int sn_dma_supported(struct device *dev, u64 mask)
35 BUG_ON(dev->bus != &pci_bus_type);
37 if (mask < 0x7fffffff)
38 return 0;
39 return 1;
41 EXPORT_SYMBOL(sn_dma_supported);
43 /**
44 * sn_dma_set_mask - set the DMA mask
45 * @dev: device to set
46 * @dma_mask: new mask
48 * Set @dev's DMA mask if the hw supports it.
50 int sn_dma_set_mask(struct device *dev, u64 dma_mask)
52 BUG_ON(dev->bus != &pci_bus_type);
54 if (!sn_dma_supported(dev, dma_mask))
55 return 0;
57 *dev->dma_mask = dma_mask;
58 return 1;
60 EXPORT_SYMBOL(sn_dma_set_mask);
62 /**
63 * sn_dma_alloc_coherent - allocate memory for coherent DMA
64 * @dev: device to allocate for
65 * @size: size of the region
66 * @dma_handle: DMA (bus) address
67 * @flags: memory allocation flags
69 * dma_alloc_coherent() returns a pointer to a memory region suitable for
70 * coherent DMA traffic to/from a PCI device. On SN platforms, this means
71 * that @dma_handle will have the %PCIIO_DMA_CMD flag set.
73 * This interface is usually used for "command" streams (e.g. the command
74 * queue for a SCSI controller). See Documentation/DMA-API.txt for
75 * more information.
77 void *sn_dma_alloc_coherent(struct device *dev, size_t size,
78 dma_addr_t * dma_handle, gfp_t flags)
80 void *cpuaddr;
81 unsigned long phys_addr;
82 int node;
83 struct pci_dev *pdev = to_pci_dev(dev);
84 struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
86 BUG_ON(dev->bus != &pci_bus_type);
89 * Allocate the memory.
91 node = pcibus_to_node(pdev->bus);
92 if (likely(node >=0)) {
93 struct page *p = alloc_pages_node(node, flags, get_order(size));
95 if (likely(p))
96 cpuaddr = page_address(p);
97 else
98 return NULL;
99 } else
100 cpuaddr = (void *)__get_free_pages(flags, get_order(size));
102 if (unlikely(!cpuaddr))
103 return NULL;
105 memset(cpuaddr, 0x0, size);
107 /* physical addr. of the memory we just got */
108 phys_addr = __pa(cpuaddr);
111 * 64 bit address translations should never fail.
112 * 32 bit translations can fail if there are insufficient mapping
113 * resources.
116 *dma_handle = provider->dma_map_consistent(pdev, phys_addr, size,
117 SN_DMA_ADDR_PHYS);
118 if (!*dma_handle) {
119 printk(KERN_ERR "%s: out of ATEs\n", __func__);
120 free_pages((unsigned long)cpuaddr, get_order(size));
121 return NULL;
124 return cpuaddr;
126 EXPORT_SYMBOL(sn_dma_alloc_coherent);
129 * sn_pci_free_coherent - free memory associated with coherent DMAable region
130 * @dev: device to free for
131 * @size: size to free
132 * @cpu_addr: kernel virtual address to free
133 * @dma_handle: DMA address associated with this region
135 * Frees the memory allocated by dma_alloc_coherent(), potentially unmapping
136 * any associated IOMMU mappings.
138 void sn_dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
139 dma_addr_t dma_handle)
141 struct pci_dev *pdev = to_pci_dev(dev);
142 struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
144 BUG_ON(dev->bus != &pci_bus_type);
146 provider->dma_unmap(pdev, dma_handle, 0);
147 free_pages((unsigned long)cpu_addr, get_order(size));
149 EXPORT_SYMBOL(sn_dma_free_coherent);
152 * sn_dma_map_single - map a single page for DMA
153 * @dev: device to map for
154 * @cpu_addr: kernel virtual address of the region to map
155 * @size: size of the region
156 * @direction: DMA direction
158 * Map the region pointed to by @cpu_addr for DMA and return the
159 * DMA address.
161 * We map this to the one step pcibr_dmamap_trans interface rather than
162 * the two step pcibr_dmamap_alloc/pcibr_dmamap_addr because we have
163 * no way of saving the dmamap handle from the alloc to later free
164 * (which is pretty much unacceptable).
166 * TODO: simplify our interface;
167 * figure out how to save dmamap handle so can use two step.
169 dma_addr_t sn_dma_map_single(struct device *dev, void *cpu_addr, size_t size,
170 int direction)
172 dma_addr_t dma_addr;
173 unsigned long phys_addr;
174 struct pci_dev *pdev = to_pci_dev(dev);
175 struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
177 BUG_ON(dev->bus != &pci_bus_type);
179 phys_addr = __pa(cpu_addr);
180 dma_addr = provider->dma_map(pdev, phys_addr, size, SN_DMA_ADDR_PHYS);
181 if (!dma_addr) {
182 printk(KERN_ERR "%s: out of ATEs\n", __func__);
183 return 0;
185 return dma_addr;
187 EXPORT_SYMBOL(sn_dma_map_single);
190 * sn_dma_unmap_single - unamp a DMA mapped page
191 * @dev: device to sync
192 * @dma_addr: DMA address to sync
193 * @size: size of region
194 * @direction: DMA direction
196 * This routine is supposed to sync the DMA region specified
197 * by @dma_handle into the coherence domain. On SN, we're always cache
198 * coherent, so we just need to free any ATEs associated with this mapping.
200 void sn_dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
201 int direction)
203 struct pci_dev *pdev = to_pci_dev(dev);
204 struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
206 BUG_ON(dev->bus != &pci_bus_type);
208 provider->dma_unmap(pdev, dma_addr, direction);
210 EXPORT_SYMBOL(sn_dma_unmap_single);
213 * sn_dma_unmap_sg - unmap a DMA scatterlist
214 * @dev: device to unmap
215 * @sg: scatterlist to unmap
216 * @nhwentries: number of scatterlist entries
217 * @direction: DMA direction
219 * Unmap a set of streaming mode DMA translations.
221 void sn_dma_unmap_sg(struct device *dev, struct scatterlist *sgl,
222 int nhwentries, int direction)
224 int i;
225 struct pci_dev *pdev = to_pci_dev(dev);
226 struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
227 struct scatterlist *sg;
229 BUG_ON(dev->bus != &pci_bus_type);
231 for_each_sg(sgl, sg, nhwentries, i) {
232 provider->dma_unmap(pdev, sg->dma_address, direction);
233 sg->dma_address = (dma_addr_t) NULL;
234 sg->dma_length = 0;
237 EXPORT_SYMBOL(sn_dma_unmap_sg);
240 * sn_dma_map_sg - map a scatterlist for DMA
241 * @dev: device to map for
242 * @sg: scatterlist to map
243 * @nhwentries: number of entries
244 * @direction: direction of the DMA transaction
246 * Maps each entry of @sg for DMA.
248 int sn_dma_map_sg(struct device *dev, struct scatterlist *sgl, int nhwentries,
249 int direction)
251 unsigned long phys_addr;
252 struct scatterlist *saved_sg = sgl, *sg;
253 struct pci_dev *pdev = to_pci_dev(dev);
254 struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
255 int i;
257 BUG_ON(dev->bus != &pci_bus_type);
260 * Setup a DMA address for each entry in the scatterlist.
262 for_each_sg(sgl, sg, nhwentries, i) {
263 phys_addr = SG_ENT_PHYS_ADDRESS(sg);
264 sg->dma_address = provider->dma_map(pdev,
265 phys_addr, sg->length,
266 SN_DMA_ADDR_PHYS);
268 if (!sg->dma_address) {
269 printk(KERN_ERR "%s: out of ATEs\n", __func__);
272 * Free any successfully allocated entries.
274 if (i > 0)
275 sn_dma_unmap_sg(dev, saved_sg, i, direction);
276 return 0;
279 sg->dma_length = sg->length;
282 return nhwentries;
284 EXPORT_SYMBOL(sn_dma_map_sg);
286 void sn_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
287 size_t size, int direction)
289 BUG_ON(dev->bus != &pci_bus_type);
291 EXPORT_SYMBOL(sn_dma_sync_single_for_cpu);
293 void sn_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
294 size_t size, int direction)
296 BUG_ON(dev->bus != &pci_bus_type);
298 EXPORT_SYMBOL(sn_dma_sync_single_for_device);
300 void sn_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
301 int nelems, int direction)
303 BUG_ON(dev->bus != &pci_bus_type);
305 EXPORT_SYMBOL(sn_dma_sync_sg_for_cpu);
307 void sn_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
308 int nelems, int direction)
310 BUG_ON(dev->bus != &pci_bus_type);
312 EXPORT_SYMBOL(sn_dma_sync_sg_for_device);
314 int sn_dma_mapping_error(dma_addr_t dma_addr)
316 return 0;
318 EXPORT_SYMBOL(sn_dma_mapping_error);
320 char *sn_pci_get_legacy_mem(struct pci_bus *bus)
322 if (!SN_PCIBUS_BUSSOFT(bus))
323 return ERR_PTR(-ENODEV);
325 return (char *)(SN_PCIBUS_BUSSOFT(bus)->bs_legacy_mem | __IA64_UNCACHED_OFFSET);
328 int sn_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size)
330 unsigned long addr;
331 int ret;
332 struct ia64_sal_retval isrv;
335 * First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work
336 * around hw issues at the pci bus level. SGI proms older than
337 * 4.10 don't implement this.
340 SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE,
341 pci_domain_nr(bus), bus->number,
342 0, /* io */
343 0, /* read */
344 port, size, __pa(val));
346 if (isrv.status == 0)
347 return size;
350 * If the above failed, retry using the SAL_PROBE call which should
351 * be present in all proms (but which cannot work round PCI chipset
352 * bugs). This code is retained for compatibility with old
353 * pre-4.10 proms, and should be removed at some point in the future.
356 if (!SN_PCIBUS_BUSSOFT(bus))
357 return -ENODEV;
359 addr = SN_PCIBUS_BUSSOFT(bus)->bs_legacy_io | __IA64_UNCACHED_OFFSET;
360 addr += port;
362 ret = ia64_sn_probe_mem(addr, (long)size, (void *)val);
364 if (ret == 2)
365 return -EINVAL;
367 if (ret == 1)
368 *val = -1;
370 return size;
373 int sn_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size)
375 int ret = size;
376 unsigned long paddr;
377 unsigned long *addr;
378 struct ia64_sal_retval isrv;
381 * First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work
382 * around hw issues at the pci bus level. SGI proms older than
383 * 4.10 don't implement this.
386 SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE,
387 pci_domain_nr(bus), bus->number,
388 0, /* io */
389 1, /* write */
390 port, size, __pa(&val));
392 if (isrv.status == 0)
393 return size;
396 * If the above failed, retry using the SAL_PROBE call which should
397 * be present in all proms (but which cannot work round PCI chipset
398 * bugs). This code is retained for compatibility with old
399 * pre-4.10 proms, and should be removed at some point in the future.
402 if (!SN_PCIBUS_BUSSOFT(bus)) {
403 ret = -ENODEV;
404 goto out;
407 /* Put the phys addr in uncached space */
408 paddr = SN_PCIBUS_BUSSOFT(bus)->bs_legacy_io | __IA64_UNCACHED_OFFSET;
409 paddr += port;
410 addr = (unsigned long *)paddr;
412 switch (size) {
413 case 1:
414 *(volatile u8 *)(addr) = (u8)(val);
415 break;
416 case 2:
417 *(volatile u16 *)(addr) = (u16)(val);
418 break;
419 case 4:
420 *(volatile u32 *)(addr) = (u32)(val);
421 break;
422 default:
423 ret = -EINVAL;
424 break;
426 out:
427 return ret;