[PATCH v2 6/9] env: Enable SPI flash env for SiFive FU540

[Jagan Teki]

SPI flash device on HiFive Unleashed has 32MiB Size.

This patch add SPI flash environment after U-Boot proper
partition with a size of 128KiB.

SPI flash partition layout(32MiB):
    0 - 34	: reserved for GPT header
   35 - 39	: unused
   40 - 2087	: loader1 (SPL, FSBL)
 2088 - 10279	: loader2 (U-Boot proper, U-Boot)
10280 - 10535	: environment
10536 - 65494	: rootfs
65528 - 65536	: distro script

Note: the loader1 must start from 40th sector even though
there are 6 free sectors prior since 40th sector is nearest
flash sector boundary. 

Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
Changes for v2:
- move env offsets from generic to cpu Kconfig

 arch/riscv/cpu/fu540/Kconfig | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/riscv/cpu/fu540/Kconfig b/arch/riscv/cpu/fu540/Kconfig
index 7a813a9ac8..417926d2cf 100644
--- a/arch/riscv/cpu/fu540/Kconfig
+++ b/arch/riscv/cpu/fu540/Kconfig
@@ -15,3 +15,16 @@ config SIFIVE_FU540
 	imply SPL_CPU_SUPPORT
 	imply SPL_OPENSBI
 	imply SPL_LOAD_FIT
+
+if CONFIG_ENV_IS_IN_SPI_FLASH
+
+config ENV_OFFSET
+	default 0x505000
+
+config ENV_SIZE
+	default 0x20000
+
+config ENV_SECT_SIZE
+	default 0x10000
+
+endif # CONFIG_ENV_IS_IN_SPI_FLASH
-- 
2.20.1