sys/dev/drm/i915/intel_acpi.c

   1 /*
   2  * Intel ACPI functions
   3  *
   4  * _DSM related code stolen from nouveau_acpi.c.
   5  */
   6 #include <linux/pci.h>
   7
   8 #include <drm/drmP.h>
   9 #include "i915_drv.h"
  10
  11 #define INTEL_DSM_REVISION_ID 1 /* For Calpella anyway... */
  12
  13 #define INTEL_DSM_FN_SUPPORTED_FUNCTIONS 0 /* No args */
  14 #define INTEL_DSM_FN_PLATFORM_MUX_INFO 1 /* No args */
  15
  16 #if 0
  17 static struct intel_dsm_priv {
  18         acpi_handle dhandle;
  19 } intel_dsm_priv;
  20
  21 static const u8 intel_dsm_guid[] = {
  22         0xd3, 0x73, 0xd8, 0x7e,
  23         0xd0, 0xc2,
  24         0x4f, 0x4e,
  25         0xa8, 0x54,
  26         0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c
  27 };
  28
  29 static int intel_dsm(acpi_handle handle, int func, int arg)
  30 {
  31         struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
  32         struct acpi_object_list input;
  33         union acpi_object params[4];
  34         union acpi_object *obj;
  35         u32 result;
  36         int ret = 0;
  37
  38         input.count = 4;
  39         input.pointer = params;
  40         params[0].type = ACPI_TYPE_BUFFER;
  41         params[0].buffer.length = sizeof(intel_dsm_guid);
  42         params[0].buffer.pointer = (char *)intel_dsm_guid;
  43         params[1].type = ACPI_TYPE_INTEGER;
  44         params[1].integer.value = INTEL_DSM_REVISION_ID;
  45         params[2].type = ACPI_TYPE_INTEGER;
  46         params[2].integer.value = func;
  47         params[3].type = ACPI_TYPE_INTEGER;
  48         params[3].integer.value = arg;
  49
  50         ret = acpi_evaluate_object(handle, "_DSM", &input, &output);
  51         if (ret) {
  52                 DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);
  53                 return ret;
  54         }
  55
  56         obj = (union acpi_object *)output.pointer;
  57
  58         result = 0;
  59         switch (obj->type) {
  60         case ACPI_TYPE_INTEGER:
  61                 result = obj->integer.value;
  62                 break;
  63
  64         case ACPI_TYPE_BUFFER:
  65                 if (obj->buffer.length == 4) {
  66                         result = (obj->buffer.pointer[0] |
  67                                 (obj->buffer.pointer[1] <<  8) |
  68                                 (obj->buffer.pointer[2] << 16) |
  69                                 (obj->buffer.pointer[3] << 24));
  70                         break;
  71                 }
  72         default:
  73                 ret = -EINVAL;
  74                 break;
  75         }
  76         if (result == 0x80000002)
  77                 ret = -ENODEV;
  78
  79         kfree(output.pointer);
  80         return ret;
  81 }
  82
  83 static char *intel_dsm_port_name(u8 id)
  84 {
  85         switch (id) {
  86         case 0:
  87                 return "Reserved";
  88         case 1:
  89                 return "Analog VGA";
  90         case 2:
  91                 return "LVDS";
  92         case 3:
  93                 return "Reserved";
  94         case 4:
  95                 return "HDMI/DVI_B";
  96         case 5:
  97                 return "HDMI/DVI_C";
  98         case 6:
  99                 return "HDMI/DVI_D";
 100         case 7:
 101                 return "DisplayPort_A";
 102         case 8:
 103                 return "DisplayPort_B";
 104         case 9:
 105                 return "DisplayPort_C";
 106         case 0xa:
 107                 return "DisplayPort_D";
 108         case 0xb:
 109         case 0xc:
 110         case 0xd:
 111                 return "Reserved";
 112         case 0xe:
 113                 return "WiDi";
 114         default:
 115                 return "bad type";
 116         }
 117 }
 118
 119 static char *intel_dsm_mux_type(u8 type)
 120 {
 121         switch (type) {
 122         case 0:
 123                 return "unknown";
 124         case 1:
 125                 return "No MUX, iGPU only";
 126         case 2:
 127                 return "No MUX, dGPU only";
 128         case 3:
 129                 return "MUXed between iGPU and dGPU";
 130         default:
 131                 return "bad type";
 132         }
 133 }
 134
 135 static void intel_dsm_platform_mux_info(void)
 136 {
 137         struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
 138         struct acpi_object_list input;
 139         union acpi_object params[4];
 140         union acpi_object *pkg;
 141         int i, ret;
 142
 143         input.count = 4;
 144         input.pointer = params;
 145         params[0].type = ACPI_TYPE_BUFFER;
 146         params[0].buffer.length = sizeof(intel_dsm_guid);
 147         params[0].buffer.pointer = (char *)intel_dsm_guid;
 148         params[1].type = ACPI_TYPE_INTEGER;
 149         params[1].integer.value = INTEL_DSM_REVISION_ID;
 150         params[2].type = ACPI_TYPE_INTEGER;
 151         params[2].integer.value = INTEL_DSM_FN_PLATFORM_MUX_INFO;
 152         params[3].type = ACPI_TYPE_INTEGER;
 153         params[3].integer.value = 0;
 154
 155         ret = acpi_evaluate_object(intel_dsm_priv.dhandle, "_DSM", &input,
 156                                    &output);
 157         if (ret) {
 158                 DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);
 159                 goto out;
 160         }
 161
 162         pkg = (union acpi_object *)output.pointer;
 163
 164         if (pkg->type == ACPI_TYPE_PACKAGE) {
 165                 union acpi_object *connector_count = &pkg->package.elements[0];
 166                 DRM_DEBUG_DRIVER("MUX info connectors: %lld\n",
 167                           (unsigned long long)connector_count->integer.value);
 168                 for (i = 1; i < pkg->package.count; i++) {
 169                         union acpi_object *obj = &pkg->package.elements[i];
 170                         union acpi_object *connector_id =
 171                                 &obj->package.elements[0];
 172                         union acpi_object *info = &obj->package.elements[1];
 173                         DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n",
 174                                   (unsigned long long)connector_id->integer.value);
 175                         DRM_DEBUG_DRIVER("  port id: %s\n",
 176                                intel_dsm_port_name(info->buffer.pointer[0]));
 177                         DRM_DEBUG_DRIVER("  display mux info: %s\n",
 178                                intel_dsm_mux_type(info->buffer.pointer[1]));
 179                         DRM_DEBUG_DRIVER("  aux/dc mux info: %s\n",
 180                                intel_dsm_mux_type(info->buffer.pointer[2]));
 181                         DRM_DEBUG_DRIVER("  hpd mux info: %s\n",
 182                                intel_dsm_mux_type(info->buffer.pointer[3]));
 183                 }
 184         }
 185
 186 out:
 187         kfree(output.pointer);
 188 }
 189
 190 static bool intel_dsm_pci_probe(struct pci_dev *pdev)
 191 {
 192         acpi_handle dhandle, intel_handle;
 193         acpi_status status;
 194         int ret;
 195
 196         dhandle = DEVICE_ACPI_HANDLE(&pdev->dev);
 197         if (!dhandle)
 198                 return false;
 199
 200         status = acpi_get_handle(dhandle, "_DSM", &intel_handle);
 201         if (ACPI_FAILURE(status)) {
 202                 DRM_DEBUG_KMS("no _DSM method for intel device\n");
 203                 return false;
 204         }
 205
 206         ret = intel_dsm(dhandle, INTEL_DSM_FN_SUPPORTED_FUNCTIONS, 0);
 207         if (ret < 0) {
 208                 DRM_DEBUG_KMS("failed to get supported _DSM functions\n");
 209                 return false;
 210         }
 211
 212         intel_dsm_priv.dhandle = dhandle;
 213
 214         intel_dsm_platform_mux_info();
 215         return true;
 216 }
 217
 218 static bool intel_dsm_detect(void)
 219 {
 220         char acpi_method_name[255] = { 0 };
 221         struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
 222         struct pci_dev *pdev = NULL;
 223         bool has_dsm = false;
 224         int vga_count = 0;
 225
 226         while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
 227                 vga_count++;
 228                 has_dsm |= intel_dsm_pci_probe(pdev);
 229         }
 230
 231         if (vga_count == 2 && has_dsm) {
 232                 acpi_get_name(intel_dsm_priv.dhandle, ACPI_FULL_PATHNAME, &buffer);
 233                 DRM_DEBUG_DRIVER("VGA switcheroo: detected DSM switching method %s handle\n",
 234                                  acpi_method_name);
 235                 return true;
 236         }
 237
 238         return false;
 239 }
 240
 241 void intel_register_dsm_handler(void)
 242 {
 243         if (!intel_dsm_detect())
 244                 return;
 245 }
 246 #endif
 247
 248 void intel_unregister_dsm_handler(void)
 249 {
 250 }