Re: [PATCH] arm64: dts: ti: k3-am64-main: Add SYSFW reserved ranges in OCRAM
From: Nishanth Menon <nm@ti.com>
Date: 2021-06-14 14:29:09
Also in:
linux-arm-kernel, lkml
On 10:18-20210614, Aswath Govindraju wrote:
Hi Vignesh, On 12/06/21 12:51 pm, Vignesh Raghavendra wrote:quoted
+Aswath On 6/12/21 12:46 AM, Nishanth Menon wrote:quoted
On 19:36-20210609, Vignesh Raghavendra wrote:quoted
Last 256K of OCRAM (256K@0x701c0000) is reserved for SYSFW usage. Hence add an entry in DT so that its not used for generic pool memory allocation.Are you really sure?? I know that I had set a budget for 16K in sysfw when I did the memory split up for sysfw of which 16k is actually used. Not sure where this 256K bucket started off from.. am I missing something here?Per: http://software-dl.ti.com/tisci/esd/latest/5_soc_doc/am64x/firewalls.html 24 dmsc 0x44060000 0x4407BFFF dmsc,rwcd // alias for 0x701E0000 24 dmsc 0x701FC000 0x701FFFFF sproxy_private,rwcd 24 dmsc 0x4407C000 0x4407FFFF sproxy_private,rwcd 24 dmsc 0x701C0000 0x701DFFFF everyone,rwcd So it looks like only 128K@0x701E0000 is firewalled off. Will update the patch. This makes me wonder why ATF is being moved to 0x701a0000-0x701c0000 leaving a hole at 0x701C0000-0x701DFFFF?The reason for leaving the hole at 0x701C0000-0x701DFFFF was because initially there was a bug in SYSFW which lead to the usage of the above region too by it. However, this bug was recently fixed and the the above region can be used for ATF.
OK. I am going to drop the TF-A update patch from my queue. NOTE: a) Default device configuration (if no specific API call[1]) is done assumes last 128K is reserved. b) if bootloader does invoke optionally a call[1] then only 16K is reserved for communication and remainder of 128K is released for usage with the constraint that TF-A/OPTEE takes control of security resources. c) This is only a feature in AM64x devices so, handling is device specific. Hence, on AM64x: (a) should be our default configuration and (b) can be board specific configuration OR overlay depending on bootloader capability. [1] http://downloads.ti.com/tisci/esd/latest/6_topic_user_guides/security_handover.html#triggering-security-handover -- Regards, Nishanth Menon Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3 1A34 DDB5 849D 1736 249D