1 /*
2  * Copyright 2012 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the
6  * "Software"), to deal in the Software without restriction, including
7  * without limitation the rights to use, copy, modify, merge, publish,
8  * distribute, sub license, and/or sell copies of the Software, and to
9  * permit persons to whom the Software is furnished to do so, subject to
10  * the following conditions:
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
14  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
15  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
16  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
17  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
18  * USE OR OTHER DEALINGS IN THE SOFTWARE.
19  *
20  * The above copyright notice and this permission notice (including the
21  * next paragraph) shall be included in all copies or substantial portions
22  * of the Software.
23  *
24  */
25 /*
26  * Authors: Dave Airlie <airlied@redhat.com>
27  */
28 
29 #include <linux/pci.h>
30 
31 #include <drm/drm_managed.h>
32 
33 #include "mgag200_drv.h"
34 
mgag200_probe_vram(struct mga_device * mdev,void __iomem * mem,size_t size)35 static size_t mgag200_probe_vram(struct mga_device *mdev, void __iomem *mem,
36 				 size_t size)
37 {
38 	int offset;
39 	int orig;
40 	int test1, test2;
41 	int orig1, orig2;
42 	size_t vram_size;
43 
44 	/* Probe */
45 	orig = ioread16(mem);
46 	iowrite16(0, mem);
47 
48 	vram_size = size;
49 
50 	if ((mdev->type == G200_EW3) && (vram_size >= 0x1000000))
51 		vram_size = vram_size - 0x400000;
52 
53 	for (offset = 0x100000; offset < vram_size; offset += 0x4000) {
54 		orig1 = ioread8(mem + offset);
55 		orig2 = ioread8(mem + offset + 0x100);
56 
57 		iowrite16(0xaa55, mem + offset);
58 		iowrite16(0xaa55, mem + offset + 0x100);
59 
60 		test1 = ioread16(mem + offset);
61 		test2 = ioread16(mem);
62 
63 		iowrite16(orig1, mem + offset);
64 		iowrite16(orig2, mem + offset + 0x100);
65 
66 		if (test1 != 0xaa55)
67 			break;
68 
69 		if (test2)
70 			break;
71 	}
72 
73 	iowrite16(orig, mem);
74 
75 	return offset - 65536;
76 }
77 
mgag200_mm_init(struct mga_device * mdev)78 int mgag200_mm_init(struct mga_device *mdev)
79 {
80 	struct drm_device *dev = &mdev->base;
81 	struct pci_dev *pdev = to_pci_dev(dev->dev);
82 	u8 misc;
83 	resource_size_t start, len;
84 
85 	WREG_ECRT(0x04, 0x00);
86 
87 	misc = RREG8(MGA_MISC_IN);
88 	misc |= MGAREG_MISC_RAMMAPEN |
89 		MGAREG_MISC_HIGH_PG_SEL;
90 	WREG8(MGA_MISC_OUT, misc);
91 
92 	/* BAR 0 is VRAM */
93 	start = pci_resource_start(pdev, 0);
94 	len = pci_resource_len(pdev, 0);
95 
96 	if (!devm_request_mem_region(dev->dev, start, len, "mgadrmfb_vram")) {
97 		drm_err(dev, "can't reserve VRAM\n");
98 		return -ENXIO;
99 	}
100 
101 	/* Don't fail on errors, but performance might be reduced. */
102 	devm_arch_io_reserve_memtype_wc(dev->dev, start, len);
103 	devm_arch_phys_wc_add(dev->dev, start, len);
104 
105 	mdev->vram = devm_ioremap(dev->dev, start, len);
106 	if (!mdev->vram)
107 		return -ENOMEM;
108 
109 	mdev->mc.vram_size = mgag200_probe_vram(mdev, mdev->vram, len);
110 	mdev->mc.vram_base = start;
111 	mdev->mc.vram_window = len;
112 
113 	mdev->vram_fb_available = mdev->mc.vram_size;
114 
115 	return 0;
116 }
117