Ticket #512 (Fixed)Fri May 14 13:43:00 UTC 2021
CM4 with eMMc
| Reported by: | Chris Hall (132) | Severity: | Enhancement |
| Part: | RISC OS: General | Release: | |
| Milestone: | Status | Fixed |
Details by Chris Hall (132):
The on-board eMMc is said to be connected via an 8bit bus using eMMc2 and so although RISC OS will boot, sometimes giving an abort error as it drops to the supervisor prompt, clicking on the SDFS::4 icon gives ‘disc drive is empty’.
Changelog:
Modified by Chris Hall (132) Fri, June 04 2021 - 08:17:49 GMT
- Severity changed from Normal to Major
- Part changed from Unspecified to RISC OS: General
Modified by Chris Hall (132) Tue, January 24 2023 - 18:12:15 GMT
Since the ROM changes on 21 Jan 2023, the eMMc on the CM4 now works almost correctly. The eMMc drive shows up as SDFS::0 and the SD card on the CM4 Lite shows up as SDFS::4. It therefore correctly discriminates but incorrectly.
Modified by Chris Hall (132) Wed, February 01 2023 - 08:17:38 GMT
- Status changed from Open to Fixed
Since the ROM changes on 1 Feb 2023 the eMMc on CM4 now works correctly.
Modified by Chris Hall (132) Mon, June 19 2023 - 15:50:34 GMT
- Status changed from Fixed to Open
There is now a documented way of discovering whether the CM4 has WiFi and/or eMMc fitted. The command vcgencmd otp_dump will show both revision code (at word 30) and extd revision code (at word 33). For the CM4 bits 31 and 30 of word 33 indicate whether WiFi (bit 31) or eMMc (bit 30) are fitted (zero = fitted). This can be used to decide whether the SDFS drive should be 0 or 4.
Modified by Chris Hall (132) Mon, June 19 2023 - 15:51:50 GMT
- Severity changed from Major to Enhancement
Modified by Sprow (202) Fri, July 14 2023 - 10:50:28 GMT
> The command vcgencmd otp_dump will show both revision code (at word 30) and extd revision code (at word 33).
That’s not much help for the HAL, it can’t run vcgencmd’s as that requires a whole load of other stuff to be up. The HAL needs to read some memory location, any idea what address the data is at? My understanding is the OTP fuses are in the VideoCore’s memory for security reasons, but if it’s copied them into RAM somewhere we could look that’d be OK.
Modified by Chris Hall (132) Thu, February 29 2024 - 14:49:11 GMT
The mailbox property GET_BOARD_REVISION &10002 now returns either 4 bytes or 8 bytes – revision code or revision code plus extended revision code. This allows CM4 Lite to be distinguished from eMMc-fitted CM4 and the call is available to the HAL in Start.ELF versions from now onwards.
Modified by Sprow (202) Thu, March 21 2024 - 15:00:35 GMT
- Status changed from Open to Fixed
HAL_BCM2835-1_04 uses the recently added firmware property from Pi boot firmware from 29-Feb-2024 (or later) in order to get the eMMC detection right.
