[PATCH] soc: renesas: make ARCH_R9A07G043 (riscv version) depend on NONPORTABLE

[Jisheng Zhang]

Drew found "CONFIG_DMA_GLOBAL_POOL=y causes ADMA buffer alloc to fail"
the log looks like:
[    3.741083] mmc0: Unable to allocate ADMA buffers - falling back to standard DMA

The logic is: generic riscv defconfig selects ARCH_RENESAS then
ARCH_R9A07G043 which selects DMA_GLOBAL_POOL, which assumes all
non-dma-coherent riscv platforms have a dma global pool, this assumption
seems not correct. And I believe DMA_GLOBAL_POOL should not be
selected by ARCH_SOCFAMILIY, instead, only ARCH under some specific
conditions can select it globaly, for example NOMMU ARM and so on,
because it's designed for special cases such as "nommu cases where
non-cacheable memory lives in a fixed place in the physical address
map" as pointed out by Robin.

Fix the issue by making ARCH_R9A07G043 (riscv version) depend on
NONPORTABLE, thus generic defconfig won't select ARCH_R9A07G043 by
default. And even for random config case, there will be less debug
effort once we see NONPORTABLE is enabled.

Reported-by: Drew Fustini <dfustini at baylibre.com>
Closes: https://lore.kernel.org/linux-riscv/ZRuamJuShOnvP1pr@x1/
Fixes: 484861e09f3e ("soc: renesas: Kconfig: Select the required configs for RZ/Five SoC")
Signed-off-by: Jisheng Zhang <jszhang at kernel.org>
---
 drivers/soc/renesas/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/soc/renesas/Kconfig b/drivers/soc/renesas/Kconfig
index 5a75ab64d1ed..12040ce116a5 100644
--- a/drivers/soc/renesas/Kconfig
+++ b/drivers/soc/renesas/Kconfig
@@ -333,6 +333,7 @@ if RISCV
 
 config ARCH_R9A07G043
 	bool "RISC-V Platform support for RZ/Five"
+	depends on NONPORTABLE
 	select ARCH_RZG2L
 	select AX45MP_L2_CACHE if RISCV_DMA_NONCOHERENT
 	select DMA_GLOBAL_POOL
-- 
2.40.1