drivers: ddr: introduce DDR driver for i.MX8M

Introduce DDR driver for i.MX8M. The driver will be used by SPL to
initialze DDR PHY and DDR Controller.

Signed-off-by: Peng Fan <[email protected]>

drivers/Makefile

@@ -34,6 +34,7 @@ obj-$(CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT) += ddr/fsl/
 obj-$(CONFIG_ARMADA_38X) += ddr/marvell/a38x/
 obj-$(CONFIG_ARMADA_XP) += ddr/marvell/axp/
 obj-$(CONFIG_ALTERA_SDRAM) += ddr/altera/
+obj-$(CONFIG_ARCH_IMX8M) += ddr/imx/imx8m/
 obj-$(CONFIG_SPL_POWER_SUPPORT) += power/ power/pmic/
 obj-$(CONFIG_SPL_POWER_SUPPORT) += power/regulator/
 obj-$(CONFIG_SPL_POWER_DOMAIN) += power/domain/

drivers/ddr/Kconfig

@@ -1 +1,2 @@
 source "drivers/ddr/altera/Kconfig"
+source "drivers/ddr/imx/Kconfig"

drivers/ddr/imx/Kconfig

@@ -0,0 +1 @@
+source "drivers/ddr/imx/imx8m/Kconfig"

drivers/ddr/imx/imx8m/Kconfig

@@ -0,0 +1,22 @@
+config IMX8M_DRAM
+	bool "imx8m dram"
+
+config IMX8M_LPDDR4
+	bool "imx8m lpddr4"
+	select IMX8M_DRAM
+	help
+	  Select the i.MX8M LPDDR4 driver support on i.MX8M SOC.
+
+config IMX8M_DDR4
+	bool "imx8m ddr4"
+	select IMX8M_DRAM
+	help
+	  Select the i.MX8M DDR4 driver support on i.MX8M SOC.
+
+config SAVED_DRAM_TIMING_BASE
+	hex "Define the base address for saved dram timing"
+	help
+	  after DRAM is trained, need to save the dram related timming
+	  info into memory for low power use. OCRAM_S is used for this
+	  purpose on i.MX8MM.
+	default 0x180000

drivers/ddr/imx/imx8m/Makefile

@@ -0,0 +1,11 @@
+#
+# Copyright 2018 NXP
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+ifdef CONFIG_SPL_BUILD
+obj-$(CONFIG_IMX8M_DRAM) += helper.o ddrphy_utils.o ddrphy_train.o ddrphy_csr.o
+obj-$(CONFIG_IMX8M_LPDDR4) += lpddr4_init.o
+obj-$(CONFIG_IMX8M_DDR4) += ddr4_init.o
+endif

drivers/ddr/imx/imx8m/ddr4_init.c

@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2018 NXP
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <asm/arch/ddr.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/imx8m_ddr.h>
+#include <asm/arch/sys_proto.h>
+
+void ddr4_cfg_umctl2(struct dram_cfg_param *ddrc_cfg, int num)
+{
+	int i = 0;
+
+	for (i = 0; i < num; i++) {
+		reg32_write(ddrc_cfg->reg, ddrc_cfg->val);
+		ddrc_cfg++;
+	}
+}
+
+void ddr_init(struct dram_timing_info *dram_timing)
+{
+	volatile unsigned int tmp_t;
+	/*
+	 * assert [0]ddr1_preset_n, [1]ddr1_core_reset_n,
+	 * [2]ddr1_phy_reset, [3]ddr1_phy_pwrokin_n,
+	 * [4]src_system_rst_b!
+	 */
+	reg32_write(SRC_DDRC_RCR_ADDR, 0x8F00003F);
+	/* deassert [4]src_system_rst_b! */
+	reg32_write(SRC_DDRC_RCR_ADDR, 0x8F00000F);
+
+	/*
+	 * change the clock source of dram_apb_clk_root
+	 * to source 4 --800MHz/4
+	 */
+	clock_set_target_val(DRAM_APB_CLK_ROOT, CLK_ROOT_ON |
+			     CLK_ROOT_SOURCE_SEL(4) |
+			     CLK_ROOT_PRE_DIV(CLK_ROOT_PRE_DIV4));
+
+	dram_pll_init(DRAM_PLL_OUT_600M);
+
+	reg32_write(0x303A00EC, 0x0000ffff); /* PGC_CPU_MAPPING */
+	reg32setbit(0x303A00F8, 5); /* PU_PGC_SW_PUP_REQ */
+
+	/* release [0]ddr1_preset_n, [3]ddr1_phy_pwrokin_n */
+	reg32_write(SRC_DDRC_RCR_ADDR, 0x8F000006);
+
+	reg32_write(DDRC_DBG1(0), 0x00000001);
+	reg32_write(DDRC_PWRCTL(0), 0x00000001);
+
+	while (0 != (0x7 & reg32_read(DDRC_STAT(0))))
+		;
+
+	/* config the uMCTL2's registers */
+	ddr4_cfg_umctl2(dram_timing->ddrc_cfg, dram_timing->ddrc_cfg_num);
+
+	reg32_write(DDRC_RFSHCTL3(0), 0x00000001);
+	/* RESET: <ctn> DEASSERTED */
+	/* RESET: <a Port 0  DEASSERTED(0) */
+	reg32_write(SRC_DDRC_RCR_ADDR, 0x8F000004);
+	reg32_write(SRC_DDRC_RCR_ADDR, 0x8F000000);
+
+	reg32_write(DDRC_DBG1(0), 0x00000000);
+	reg32_write(DDRC_PWRCTL(0), 0x00000aa);
+	reg32_write(DDRC_SWCTL(0), 0x00000000);
+
+	reg32_write(DDRC_DFIMISC(0), 0x00000000);
+
+	/* config the DDR PHY's registers */
+	ddr_cfg_phy(dram_timing);
+
+	do {
+		tmp_t = reg32_read(IP2APB_DDRPHY_IPS_BASE_ADDR(0) +
+				   4 * 0x00020097);
+	} while (tmp_t != 0);
+
+	reg32_write(DDRC_DFIMISC(0), 0x00000020);
+
+	/* wait DFISTAT.dfi_init_complete to 1 */
+	while (0 == (0x1 & reg32_read(DDRC_DFISTAT(0))))
+		;
+
+	/* clear DFIMISC.dfi_init_complete_en */
+	reg32_write(DDRC_DFIMISC(0), 0x00000000);
+	/* set DFIMISC.dfi_init_complete_en again */
+	reg32_write(DDRC_DFIMISC(0), 0x00000001);
+	reg32_write(DDRC_PWRCTL(0), 0x0000088);
+
+	/*
+	 * set SWCTL.sw_done to enable quasi-dynamic register
+	 * programming outside reset.
+	 */
+	reg32_write(DDRC_SWCTL(0), 0x00000001);
+	/* wait SWSTAT.sw_done_ack to 1 */
+	while (0 == (0x1 & reg32_read(DDRC_SWSTAT(0))))
+		;
+
+	/* wait STAT to normal state */
+	while (0x1 != (0x7 & reg32_read(DDRC_STAT(0))))
+		;
+
+	reg32_write(DDRC_PWRCTL(0), 0x0000088);
+	reg32_write(DDRC_PCTRL_0(0), 0x00000001);
+	/* dis_auto-refresh is set to 0 */
+	reg32_write(DDRC_RFSHCTL3(0), 0x00000000);
+
+	/* save the dram timing config into memory */
+	dram_config_save(dram_timing, CONFIG_SAVED_DRAM_TIMING_BASE);
+}