projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b4bdc4fb MR |
1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* Copyright (C) 2020 Maxime Ripard <maxime@cerno.tech> */ | |
| 3 | ||
| 4 | #include <linux/device.h> | |
| e24f7fac | 5 | #include <linux/dma-map-ops.h> |
| b4bdc4fb MR |
6 | #include <linux/init.h> |
| 7 | #include <linux/notifier.h> | |
| 8 | #include <linux/of.h> | |
| 9 | #include <linux/platform_device.h> | |
| 10 | ||
| 11 | static const char * const sunxi_mbus_devices[] = { | |
| 12 | /* | |
| 13 | * The display engine virtual devices are not strictly speaking | |
| 14 | * connected to the MBUS, but since DRM will perform all the | |
| 15 | * memory allocations and DMA operations through that device, we | |
| 16 | * need to have the quirk on those devices too. | |
| 17 | */ | |
| 18 | "allwinner,sun4i-a10-display-engine", | |
| 19 | "allwinner,sun5i-a10s-display-engine", | |
| 20 | "allwinner,sun5i-a13-display-engine", | |
| 21 | "allwinner,sun6i-a31-display-engine", | |
| 22 | "allwinner,sun6i-a31s-display-engine", | |
| 23 | "allwinner,sun7i-a20-display-engine", | |
| 24 | "allwinner,sun8i-a23-display-engine", | |
| 25 | "allwinner,sun8i-a33-display-engine", | |
| b4bdc4fb | 26 | "allwinner,sun9i-a80-display-engine", |
| b4bdc4fb MR |
27 | |
| 28 | /* | |
| 29 | * And now we have the regular devices connected to the MBUS | |
| 30 | * (that we know of). | |
| 31 | */ | |
| 32 | "allwinner,sun4i-a10-csi1", | |
| 33 | "allwinner,sun4i-a10-display-backend", | |
| 34 | "allwinner,sun4i-a10-display-frontend", | |
| 35 | "allwinner,sun4i-a10-video-engine", | |
| 36 | "allwinner,sun5i-a13-display-backend", | |
| 37 | "allwinner,sun5i-a13-video-engine", | |
| 38 | "allwinner,sun6i-a31-csi", | |
| 39 | "allwinner,sun6i-a31-display-backend", | |
| 40 | "allwinner,sun7i-a20-csi0", | |
| 41 | "allwinner,sun7i-a20-display-backend", | |
| 42 | "allwinner,sun7i-a20-display-frontend", | |
| 43 | "allwinner,sun7i-a20-video-engine", | |
| 44 | "allwinner,sun8i-a23-display-backend", | |
| 45 | "allwinner,sun8i-a23-display-frontend", | |
| 46 | "allwinner,sun8i-a33-display-backend", | |
| 47 | "allwinner,sun8i-a33-display-frontend", | |
| 48 | "allwinner,sun8i-a33-video-engine", | |
| 49 | "allwinner,sun8i-a83t-csi", | |
| 50 | "allwinner,sun8i-h3-csi", | |
| 51 | "allwinner,sun8i-h3-video-engine", | |
| 52 | "allwinner,sun8i-v3s-csi", | |
| 53 | "allwinner,sun9i-a80-display-backend", | |
| 54 | "allwinner,sun50i-a64-csi", | |
| 55 | "allwinner,sun50i-a64-video-engine", | |
| 56 | "allwinner,sun50i-h5-video-engine", | |
| 57 | NULL, | |
| 58 | }; | |
| 59 | ||
| 60 | static int sunxi_mbus_notifier(struct notifier_block *nb, | |
| 61 | unsigned long event, void *__dev) | |
| 62 | { | |
| 63 | struct device *dev = __dev; | |
| 64 | int ret; | |
| 65 | ||
| 66 | if (event != BUS_NOTIFY_ADD_DEVICE) | |
| 67 | return NOTIFY_DONE; | |
| 68 | ||
| 69 | /* | |
| 70 | * Only the devices that need a large memory bandwidth do DMA | |
| 71 | * directly over the memory bus (called MBUS), instead of going | |
| 72 | * through the regular system bus. | |
| 73 | */ | |
| 74 | if (!of_device_compatible_match(dev->of_node, sunxi_mbus_devices)) | |
| 75 | return NOTIFY_DONE; | |
| 76 | ||
| 77 | /* | |
| 78 | * Devices with an interconnects property have the MBUS | |
| 79 | * relationship described in their DT and dealt with by | |
| 80 | * of_dma_configure, so we can just skip them. | |
| 81 | * | |
| 82 | * Older DTs or SoCs who are not clearly understood need to set | |
| 83 | * that DMA offset though. | |
| 84 | */ | |
| a9c6a1fc | 85 | if (of_property_present(dev->of_node, "interconnects")) |
| b4bdc4fb MR |
86 | return NOTIFY_DONE; |
| 87 | ||
| 88 | ret = dma_direct_set_offset(dev, PHYS_OFFSET, 0, SZ_4G); | |
| 89 | if (ret) | |
| 90 | dev_err(dev, "Couldn't setup our DMA offset: %d\n", ret); | |
| 91 | ||
| 92 | return NOTIFY_DONE; | |
| 93 | } | |
| 94 | ||
| 95 | static struct notifier_block sunxi_mbus_nb = { | |
| 96 | .notifier_call = sunxi_mbus_notifier, | |
| 97 | }; | |
| 98 | ||
| 99 | static const char * const sunxi_mbus_platforms[] __initconst = { | |
| 100 | "allwinner,sun4i-a10", | |
| 101 | "allwinner,sun5i-a10s", | |
| 102 | "allwinner,sun5i-a13", | |
| 103 | "allwinner,sun6i-a31", | |
| 104 | "allwinner,sun7i-a20", | |
| 105 | "allwinner,sun8i-a23", | |
| 106 | "allwinner,sun8i-a33", | |
| 107 | "allwinner,sun8i-a83t", | |
| 108 | "allwinner,sun8i-h3", | |
| 109 | "allwinner,sun8i-r40", | |
| 110 | "allwinner,sun8i-v3", | |
| 111 | "allwinner,sun8i-v3s", | |
| 112 | "allwinner,sun9i-a80", | |
| 113 | "allwinner,sun50i-a64", | |
| 114 | "allwinner,sun50i-h5", | |
| 115 | "nextthing,gr8", | |
| 116 | NULL, | |
| 117 | }; | |
| 118 | ||
| 119 | static int __init sunxi_mbus_init(void) | |
| 120 | { | |
| 121 | if (!of_device_compatible_match(of_root, sunxi_mbus_platforms)) | |
| 122 | return 0; | |
| 123 | ||
| 124 | bus_register_notifier(&platform_bus_type, &sunxi_mbus_nb); | |
| 125 | return 0; | |
| 126 | } | |
| 127 | arch_initcall(sunxi_mbus_init); |