From 335b139057ef79dbede01dea6e8c3f47c2b88802 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Mon, 16 Mar 2020 09:47:38 +0900 Subject: riscv: Add SOC early init support Add a mechanism for early SoC initialization for platforms that need additional hardware initialization not possible through the regular device tree and drivers mechanism. With this, a SoC specific initialization function can be called very early, before DTB parsing is done by parse_dtb() in Linux RISC-V kernel setup code. This can be very useful for early hardware initialization for No-MMU kernels booted directly in M-mode because it is quite likely that no other booting stage exist prior to the No-MMU kernel. Example use of a SoC early initialization is as follows: static void vendor_abc_early_init(const void *fdt) { /* * some early init code here that can use simple matches * against the flat device tree file. */ } SOC_EARLY_INIT_DECLARE("vendor,abc", abc_early_init); This early initialization function is executed only if the flat device tree for the board has a 'compatible = "vendor,abc"' entry; Signed-off-by: Damien Le Moal Signed-off-by: Anup Patel Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/head.S | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/riscv/kernel/head.S') diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index e5115d5e0b3a..98a406474e7d 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -234,6 +234,7 @@ clear_bss_done: call kasan_early_init #endif /* Start the kernel */ + call soc_early_init call parse_dtb tail start_kernel -- cgit v1.2.3