[PATCH next v6 06/12] clk: ast2600: Add RSACLK control for ACRY

[Chia-Wei Wang]

Add RSACLK enable for ACRY, the HW RSA/ECC crypto engine
of ASPEED AST2600 SoCs.

As ACRY and HACE share the same reset control bit, we do not
perform the reset-hold-n-release operation during their clock
ungating process. Instead, only reset release is conducted to
prevent mutual interference.

Signed-off-by: Chia-Wei Wang <chiawei_w...@aspeedtech.com>
---
 .../arm/include/asm/arch-aspeed/scu_ast2600.h |  1 +
 drivers/clk/aspeed/clk_ast2600.c              | 22 +++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/arch/arm/include/asm/arch-aspeed/scu_ast2600.h 
b/arch/arm/include/asm/arch-aspeed/scu_ast2600.h
index d7b500f656..7c5aab98b6 100644
--- a/arch/arm/include/asm/arch-aspeed/scu_ast2600.h
+++ b/arch/arm/include/asm/arch-aspeed/scu_ast2600.h
@@ -8,6 +8,7 @@
 #define SCU_UNLOCK_KEY                 0x1688a8a8
 
 #define SCU_CLKGATE1_EMMC                      BIT(27)
+#define SCU_CLKGATE1_ACRY                      BIT(24)
 #define SCU_CLKGATE1_MAC2                      BIT(21)
 #define SCU_CLKGATE1_MAC1                      BIT(20)
 #define SCU_CLKGATE1_USB_HUB                   BIT(14)
diff --git a/drivers/clk/aspeed/clk_ast2600.c b/drivers/clk/aspeed/clk_ast2600.c
index 69128fd3c4..f6ebf824aa 100644
--- a/drivers/clk/aspeed/clk_ast2600.c
+++ b/drivers/clk/aspeed/clk_ast2600.c
@@ -1018,11 +1018,26 @@ static ulong ast2600_enable_haceclk(struct ast2600_scu 
*scu)
        uint32_t reset_bit;
        uint32_t clkgate_bit;
 
+       /* share the same reset control bit with ACRY */
        reset_bit = BIT(ASPEED_RESET_HACE);
        clkgate_bit = SCU_CLKGATE1_HACE;
 
-       writel(reset_bit, &scu->modrst_ctrl1);
-       udelay(100);
+       writel(clkgate_bit, &scu->clkgate_clr1);
+       mdelay(20);
+       writel(reset_bit, &scu->modrst_clr1);
+
+       return 0;
+}
+
+static ulong ast2600_enable_rsaclk(struct ast2600_scu *scu)
+{
+       uint32_t reset_bit;
+       uint32_t clkgate_bit;
+
+       /* share the same reset control bit with HACE */
+       reset_bit = BIT(ASPEED_RESET_HACE);
+       clkgate_bit = SCU_CLKGATE1_ACRY;
+
        writel(clkgate_bit, &scu->clkgate_clr1);
        mdelay(20);
        writel(reset_bit, &scu->modrst_clr1);
@@ -1071,6 +1086,9 @@ static int ast2600_clk_enable(struct clk *clk)
        case ASPEED_CLK_GATE_YCLK:
                ast2600_enable_haceclk(priv->scu);
                break;
+       case ASPEED_CLK_GATE_RSACLK:
+               ast2600_enable_rsaclk(priv->scu);
+               break;
        default:
                pr_err("can't enable clk\n");
                return -ENOENT;
-- 
2.17.1