xref: /freebsd/sys/dev/drm2/drm_pci.c (revision 5dd76dd0cc19450133aa379ce0ce4a68ae07fb39)
1 /*-
2  * Copyright 2003 Eric Anholt.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
19  * AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
21  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <sys/cdefs.h>
25 __FBSDID("$FreeBSD$");
26 
27 /**
28  * \file drm_pci.h
29  * \brief PCI consistent, DMA-accessible memory allocation.
30  *
31  * \author Eric Anholt <anholt@FreeBSD.org>
32  */
33 
34 #include <dev/drm2/drmP.h>
35 
36 /**********************************************************************/
37 /** \name PCI memory */
38 /*@{*/
39 
40 static void
41 drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
42 {
43 	drm_dma_handle_t *dmah = arg;
44 
45 	if (error != 0)
46 		return;
47 
48 	KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count"));
49 	dmah->busaddr = segs[0].ds_addr;
50 }
51 
52 /**
53  * \brief Allocate a physically contiguous DMA-accessible consistent
54  * memory block.
55  */
56 drm_dma_handle_t *
57 drm_pci_alloc(struct drm_device *dev, size_t size,
58 	      size_t align, dma_addr_t maxaddr)
59 {
60 	drm_dma_handle_t *dmah;
61 	int ret;
62 
63 	/* Need power-of-two alignment, so fail the allocation if it isn't. */
64 	if ((align & (align - 1)) != 0) {
65 		DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n",
66 		    (int)align);
67 		return NULL;
68 	}
69 
70 	dmah = malloc(sizeof(drm_dma_handle_t), DRM_MEM_DMA, M_ZERO | M_NOWAIT);
71 	if (dmah == NULL)
72 		return NULL;
73 
74 	/* Make sure we aren't holding mutexes here */
75 	mtx_assert(&dev->dma_lock, MA_NOTOWNED);
76 	if (mtx_owned(&dev->dma_lock))
77 	    DRM_ERROR("called while holding dma_lock\n");
78 
79 	ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
80 	    maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
81 	    NULL, NULL, /* filtfunc, filtfuncargs */
82 	    size, 1, size, /* maxsize, nsegs, maxsegsize */
83 	    0, NULL, NULL, /* flags, lockfunc, lockfuncargs */
84 	    &dmah->tag);
85 	if (ret != 0) {
86 		free(dmah, DRM_MEM_DMA);
87 		return NULL;
88 	}
89 
90 	ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr,
91 	    BUS_DMA_WAITOK | BUS_DMA_ZERO | BUS_DMA_NOCACHE, &dmah->map);
92 	if (ret != 0) {
93 		bus_dma_tag_destroy(dmah->tag);
94 		free(dmah, DRM_MEM_DMA);
95 		return NULL;
96 	}
97 
98 	ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
99 	    drm_pci_busdma_callback, dmah, BUS_DMA_NOWAIT);
100 	if (ret != 0) {
101 		bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
102 		bus_dma_tag_destroy(dmah->tag);
103 		free(dmah, DRM_MEM_DMA);
104 		return NULL;
105 	}
106 
107 	return dmah;
108 }
109 
110 /**
111  * \brief Free a DMA-accessible consistent memory block.
112  */
113 void
114 drm_pci_free(struct drm_device *dev, drm_dma_handle_t *dmah)
115 {
116 	if (dmah == NULL)
117 		return;
118 
119 	bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
120 	bus_dma_tag_destroy(dmah->tag);
121 
122 	free(dmah, DRM_MEM_DMA);
123 }
124 
125 /*@}*/
126 
127 int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *mask)
128 {
129 	device_t root;
130 	int pos;
131 	u32 lnkcap = 0, lnkcap2 = 0;
132 
133 	*mask = 0;
134 	if (!drm_device_is_pcie(dev))
135 		return -EINVAL;
136 
137 	root =
138 	    device_get_parent( /* pcib             */
139 	    device_get_parent( /* `-- pci          */
140 	    device_get_parent( /*     `-- vgapci   */
141 	    dev->device)));    /*         `-- drmn */
142 
143 	pos = 0;
144 	pci_find_cap(root, PCIY_EXPRESS, &pos);
145 	if (!pos)
146 		return -EINVAL;
147 
148 	/* we've been informed via and serverworks don't make the cut */
149 	if (pci_get_vendor(root) == PCI_VENDOR_ID_VIA ||
150 	    pci_get_vendor(root) == PCI_VENDOR_ID_SERVERWORKS)
151 		return -EINVAL;
152 
153 	lnkcap = pci_read_config(root, pos + PCIER_LINK_CAP, 4);
154 	lnkcap2 = pci_read_config(root, pos + PCIER_LINK_CAP2, 4);
155 
156 	lnkcap &= PCIEM_LINK_CAP_MAX_SPEED;
157 	lnkcap2 &= 0xfe;
158 
159 #define	PCI_EXP_LNKCAP2_SLS_2_5GB 0x02	/* Supported Link Speed 2.5GT/s */
160 #define	PCI_EXP_LNKCAP2_SLS_5_0GB 0x04	/* Supported Link Speed 5.0GT/s */
161 #define	PCI_EXP_LNKCAP2_SLS_8_0GB 0x08	/* Supported Link Speed 8.0GT/s */
162 
163 	if (lnkcap2) { /* PCIE GEN 3.0 */
164 		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)
165 			*mask |= DRM_PCIE_SPEED_25;
166 		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)
167 			*mask |= DRM_PCIE_SPEED_50;
168 		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
169 			*mask |= DRM_PCIE_SPEED_80;
170 	} else {
171 		if (lnkcap & 1)
172 			*mask |= DRM_PCIE_SPEED_25;
173 		if (lnkcap & 2)
174 			*mask |= DRM_PCIE_SPEED_50;
175 	}
176 
177 	DRM_INFO("probing gen 2 caps for device %x:%x = %x/%x\n", pci_get_vendor(root), pci_get_device(root), lnkcap, lnkcap2);
178 	return 0;
179 }
180