From 413353b30b5d23c409b6a2fd70aa1cc28451a451 Mon Sep 17 00:00:00 2001 From: "maxims@google.com" Date: Mon, 17 Apr 2017 12:00:23 -0700 Subject: aspeed: Make SCU lock/unlock functions part of SCU API Make functions for locking and unlocking SCU part of SCU API. Many drivers need to modify settings in SCU and thus need to unlock it first. This change makes it possible. Signed-off-by: Maxim Sloyko Reviewed-by: Simon Glass --- arch/arm/include/asm/arch-aspeed/scu_ast2500.h | 14 ++++++++++++++ arch/arm/mach-aspeed/ast2500/clk_ast2500.c | 15 +++++++++++++++ 2 files changed, 29 insertions(+) (limited to 'arch') diff --git a/arch/arm/include/asm/arch-aspeed/scu_ast2500.h b/arch/arm/include/asm/arch-aspeed/scu_ast2500.h index fc0c01a..0fa3ecb 100644 --- a/arch/arm/include/asm/arch-aspeed/scu_ast2500.h +++ b/arch/arm/include/asm/arch-aspeed/scu_ast2500.h @@ -120,6 +120,20 @@ int ast_get_clk(struct udevice **devp); */ void *ast_get_scu(void); +/** + * ast_scu_unlock() - unlock protected registers + * + * @scu, pointer to ast2500_scu + */ +void ast_scu_unlock(struct ast2500_scu *scu); + +/** + * ast_scu_lock() - lock protected registers + * + * @scu, pointer to ast2500_scu + */ +void ast_scu_lock(struct ast2500_scu *scu); + #endif /* __ASSEMBLY__ */ #endif /* _ASM_ARCH_SCU_AST2500_H */ diff --git a/arch/arm/mach-aspeed/ast2500/clk_ast2500.c b/arch/arm/mach-aspeed/ast2500/clk_ast2500.c index 079909f..30cfac1 100644 --- a/arch/arm/mach-aspeed/ast2500/clk_ast2500.c +++ b/arch/arm/mach-aspeed/ast2500/clk_ast2500.c @@ -6,6 +6,7 @@ #include #include +#include #include int ast_get_clk(struct udevice **devp) @@ -28,3 +29,17 @@ void *ast_get_scu(void) return priv->scu; } + +void ast_scu_unlock(struct ast2500_scu *scu) +{ + writel(SCU_UNLOCK_VALUE, &scu->protection_key); + while (!readl(&scu->protection_key)) + ; +} + +void ast_scu_lock(struct ast2500_scu *scu) +{ + writel(~SCU_UNLOCK_VALUE, &scu->protection_key); + while (readl(&scu->protection_key)) + ; +} -- cgit v1.1