ARM: i.MX8MP: adapt atf bl31 base address

With i.MX8MP A1 silicon the OCRAM space is extended to 576KB whereas
the pre-release silicon has only 512KB. So the upstream TF-A adapted the
base address to move BL31 to the last 128KB of the OCRAM.

The adaption was a bit messy because each version changed it:
 - v2.4 base addr = 0x960000 (original)
 - v2.5 base addr = 0x970000 (adapted to new silicon revision)
 - v2.6 base addr = 0x960000 (changed back by accident)
 - v2.7 base addr = 0x970000 (accident fixed)

With v2.7 it is correctly set for A1 silicon onwards and we strongly
recommend to use this version or newer.

This commit also adapts the documentation for the i.MX8MP-EVK to
reference the upstream TF-A and to point out our favorite version.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Link: https://lore.barebox.org/20220704165256.589530-1-m.felsch@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Documentation/boards/imx/nxp-imx8mp-evk.rst

@@ -40,15 +40,18 @@ As a last step of this process those files need to be placed in
 	      firmware/${f}; \
   done
 
-Get and Build the ARM Trusted firmware
---------------------------------------
+Get and Build the Trusted Firmware A
+------------------------------------
 
-Get ATF from https://source.codeaurora.org/external/imx/imx-atf, branch
-imx_5.4.3_2.0.0::
+Get TF-A from https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/ and
+checkout version v2.7::
 
   make PLAT=imx8mp bl31
   cp build/imx8mp/release/bl31.bin ${barebox_srctree}/imx8mp-bl31.bin
 
+.. warning:: It is important to use a version >= v2.7 else your system
+   might not boot.
+
 Build Barebox
 -------------
 

arch/arm/mach-imx/include/mach/atf.h

@@ -10,7 +10,7 @@
 
 #define MX8MM_ATF_BL31_BASE_ADDR	0x00920000
 #define MX8MN_ATF_BL31_BASE_ADDR	0x00960000
-#define MX8MP_ATF_BL31_BASE_ADDR	0x00960000
+#define MX8MP_ATF_BL31_BASE_ADDR	0x00970000
 #define MX8MQ_ATF_BL31_BASE_ADDR	0x00910000
 #define MX8M_ATF_BL33_BASE_ADDR		0x40200000
 #define MX8MM_ATF_BL33_BASE_ADDR	MX8M_ATF_BL33_BASE_ADDR