| Rafał Miłecki | 8369ae3 | 2011-05-09 18:56:46 +0200 | [diff] [blame] | 1 | Broadcom introduced new bus as replacement for older SSB. It is based on AMBA, |
| 2 | however from programming point of view there is nothing AMBA specific we use. |
| 3 | |
| 4 | Standard AMBA drivers are platform specific, have hardcoded addresses and use |
| 5 | AMBA standard fields like CID and PID. |
| 6 | |
| 7 | In case of Broadcom's cards every device consists of: |
| 8 | 1) Broadcom specific AMBA device. It is put on AMBA bus, but can not be treated |
| 9 | as standard AMBA device. Reading it's CID or PID can cause machine lockup. |
| 10 | 2) AMBA standard devices called ports or wrappers. They have CIDs (AMBA_CID) |
| 11 | and PIDs (0x103BB369), but we do not use that info for anything. One of that |
| 12 | devices is used for managing Broadcom specific core. |
| 13 | |
| 14 | Addresses of AMBA devices are not hardcoded in driver and have to be read from |
| 15 | EPROM. |
| 16 | |
| 17 | In this situation we decided to introduce separated bus. It can contain up to |
| 18 | 16 devices identified by Broadcom specific fields: manufacturer, id, revision |
| 19 | and class. |