| Luis R. Rodriguez | 113ccc3 | 2016-12-16 03:10:36 -0800 | [diff] [blame] | 1 | ===================== |
| 2 | Firmware lookup order |
| 3 | ===================== |
| 4 | |
| 5 | Different functionality is available to enable firmware to be found. |
| 6 | Below is chronological order of how firmware will be looked for once |
| 7 | a driver issues a firmware API call. |
| 8 | |
| 9 | * The ''Built-in firmware'' is checked first, if the firmware is present we |
| 10 | return it immediately |
| 11 | * The ''Firmware cache'' is looked at next. If the firmware is found we |
| 12 | return it immediately |
| 13 | * The ''Direct filesystem lookup'' is performed next, if found we |
| 14 | return it immediately |
| Hans de Goede | e4c2c0f | 2020-01-15 17:35:48 +0100 | [diff] [blame] | 15 | * The ''Platform firmware fallback'' is performed next, but only when |
| 16 | firmware_request_platform() is used, if found we return it immediately |
| Luis R. Rodriguez | 113ccc3 | 2016-12-16 03:10:36 -0800 | [diff] [blame] | 17 | * If no firmware has been found and the fallback mechanism was enabled |
| 18 | the sysfs interface is created. After this either a kobject uevent |
| 19 | is issued or the custom firmware loading is relied upon for firmware |
| 20 | loading up to the timeout value. |
