[PATCH 36/53] imx: imx9: clock: Add DDR clock support

Peng Fan (OSS) peng.fan at oss.nxp.com
Wed Jul 20 15:17:50 CEST 2022


From: Ye Li <ye.li at nxp.com>

Implement the DDR driver clock interfaces for set DDR rate and
bypass DDR PLL

Signed-off-by: Ye Li <ye.li at nxp.com>
Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 arch/arm/include/asm/arch-imx9/clock.h |  3 ++
 arch/arm/mach-imx/imx9/clock.c         | 41 ++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/arch/arm/include/asm/arch-imx9/clock.h b/arch/arm/include/asm/arch-imx9/clock.h
index fcf04d66f05..d96f126a1d1 100644
--- a/arch/arm/include/asm/arch-imx9/clock.h
+++ b/arch/arm/include/asm/arch-imx9/clock.h
@@ -213,6 +213,9 @@ void init_clk_usdhc(u32 index);
 int enable_i2c_clk(unsigned char enable, u32 i2c_num);
 u32 imx_get_i2cclk(u32 i2c_num);
 u32 mxc_get_clock(enum mxc_clock clk);
+void dram_pll_init(ulong pll_val);
+void dram_enable_bypass(ulong clk_val);
+void dram_disable_bypass(void);
 
 int ccm_clk_src_on(enum ccm_clk_src oscpll, bool enable);
 int ccm_clk_src_auto(enum ccm_clk_src oscpll, bool enable);
diff --git a/arch/arm/mach-imx/imx9/clock.c b/arch/arm/mach-imx/imx9/clock.c
index 55cbb40f328..5d2bc0d2f8f 100644
--- a/arch/arm/mach-imx/imx9/clock.c
+++ b/arch/arm/mach-imx/imx9/clock.c
@@ -626,6 +626,47 @@ void enable_usboh3_clk(unsigned char enable)
 	}
 }
 
+#ifdef CONFIG_SPL_BUILD
+void dram_pll_init(ulong pll_val)
+{
+	configure_fracpll(DRAM_PLL_CLK, pll_val);
+}
+
+void dram_enable_bypass(ulong clk_val)
+{
+	switch (clk_val) {
+	case MHZ(400):
+		ccm_clk_root_cfg(DRAM_ALT_CLK_ROOT, SYS_PLL_PFD1, 2);
+		break;
+	case MHZ(333):
+		ccm_clk_root_cfg(DRAM_ALT_CLK_ROOT, SYS_PLL_PFD0, 3);
+		break;
+	case MHZ(200):
+		ccm_clk_root_cfg(DRAM_ALT_CLK_ROOT, SYS_PLL_PFD1, 4);
+		break;
+	case MHZ(100):
+		ccm_clk_root_cfg(DRAM_ALT_CLK_ROOT, SYS_PLL_PFD1, 8);
+		break;
+	default:
+		printf("No matched freq table %lu\n", clk_val);
+		return;
+	}
+
+	/* Set DRAM APB to 133Mhz */
+	ccm_clk_root_cfg(DRAM_APB_CLK_ROOT, SYS_PLL_PFD1_DIV2, 3);
+	/* Switch from DRAM  clock root from PLL to CCM */
+	ccm_shared_gpr_set(SHARED_GPR_DRAM_CLK, SHARED_GPR_DRAM_CLK_SEL_CCM);
+}
+
+void dram_disable_bypass(void)
+{
+	/* Set DRAM APB to 133Mhz */
+	ccm_clk_root_cfg(DRAM_APB_CLK_ROOT, SYS_PLL_PFD1_DIV2, 3);
+	/* Switch from DRAM  clock root from CCM to PLL */
+	ccm_shared_gpr_set(SHARED_GPR_DRAM_CLK, SHARED_GPR_DRAM_CLK_SEL_PLL);
+}
+#endif
+
 int clock_init(void)
 {
 	int i;
-- 
2.36.0



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