Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1535 insertions, 0 deletions

diff --git a/drivers/memory/tegra/tegra124-emc.c b/drivers/memory/tegra/tegra124-emc.c
new file mode 100644
index 0000000000..00ed2b6a0d
--- /dev/null
+++ b/drivers/memory/tegra/tegra124-emc.c
@@ -0,0 +1,1535 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Author:
+ *	Mikko Perttunen <mperttunen@nvidia.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk/tegra.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/interconnect-provider.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/sort.h>
+#include <linux/string.h>
+
+#include <soc/tegra/fuse.h>
+#include <soc/tegra/mc.h>
+
+#include "mc.h"
+
+#define EMC_FBIO_CFG5				0x104
+#define	EMC_FBIO_CFG5_DRAM_TYPE_MASK		0x3
+#define	EMC_FBIO_CFG5_DRAM_TYPE_SHIFT		0
+#define EMC_FBIO_CFG5_DRAM_WIDTH_X64		BIT(4)
+
+#define EMC_INTSTATUS				0x0
+#define EMC_INTSTATUS_CLKCHANGE_COMPLETE	BIT(4)
+
+#define EMC_CFG					0xc
+#define EMC_CFG_DRAM_CLKSTOP_PD			BIT(31)
+#define EMC_CFG_DRAM_CLKSTOP_SR			BIT(30)
+#define EMC_CFG_DRAM_ACPD			BIT(29)
+#define EMC_CFG_DYN_SREF			BIT(28)
+#define EMC_CFG_PWR_MASK			((0xF << 28) | BIT(18))
+#define EMC_CFG_DSR_VTTGEN_DRV_EN		BIT(18)
+
+#define EMC_REFCTRL				0x20
+#define EMC_REFCTRL_DEV_SEL_SHIFT		0
+#define EMC_REFCTRL_ENABLE			BIT(31)
+
+#define EMC_TIMING_CONTROL			0x28
+#define EMC_RC					0x2c
+#define EMC_RFC					0x30
+#define EMC_RAS					0x34
+#define EMC_RP					0x38
+#define EMC_R2W					0x3c
+#define EMC_W2R					0x40
+#define EMC_R2P					0x44
+#define EMC_W2P					0x48
+#define EMC_RD_RCD				0x4c
+#define EMC_WR_RCD				0x50
+#define EMC_RRD					0x54
+#define EMC_REXT				0x58
+#define EMC_WDV					0x5c
+#define EMC_QUSE				0x60
+#define EMC_QRST				0x64
+#define EMC_QSAFE				0x68
+#define EMC_RDV					0x6c
+#define EMC_REFRESH				0x70
+#define EMC_BURST_REFRESH_NUM			0x74
+#define EMC_PDEX2WR				0x78
+#define EMC_PDEX2RD				0x7c
+#define EMC_PCHG2PDEN				0x80
+#define EMC_ACT2PDEN				0x84
+#define EMC_AR2PDEN				0x88
+#define EMC_RW2PDEN				0x8c
+#define EMC_TXSR				0x90
+#define EMC_TCKE				0x94
+#define EMC_TFAW				0x98
+#define EMC_TRPAB				0x9c
+#define EMC_TCLKSTABLE				0xa0
+#define EMC_TCLKSTOP				0xa4
+#define EMC_TREFBW				0xa8
+#define EMC_ODT_WRITE				0xb0
+#define EMC_ODT_READ				0xb4
+#define EMC_WEXT				0xb8
+#define EMC_CTT					0xbc
+#define EMC_RFC_SLR				0xc0
+#define EMC_MRS_WAIT_CNT2			0xc4
+
+#define EMC_MRS_WAIT_CNT			0xc8
+#define EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT	0
+#define EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK	\
+	(0x3FF << EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT)
+#define EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT	16
+#define EMC_MRS_WAIT_CNT_LONG_WAIT_MASK		\
+	(0x3FF << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
+
+#define EMC_MRS					0xcc
+#define EMC_MODE_SET_DLL_RESET			BIT(8)
+#define EMC_MODE_SET_LONG_CNT			BIT(26)
+#define EMC_EMRS				0xd0
+#define EMC_REF					0xd4
+#define EMC_PRE					0xd8
+
+#define EMC_SELF_REF				0xe0
+#define EMC_SELF_REF_CMD_ENABLED		BIT(0)
+#define EMC_SELF_REF_DEV_SEL_SHIFT		30
+
+#define EMC_MRW					0xe8
+
+#define EMC_MRR					0xec
+#define EMC_MRR_MA_SHIFT			16
+#define LPDDR2_MR4_TEMP_SHIFT			0
+
+#define EMC_XM2DQSPADCTRL3			0xf8
+#define EMC_FBIO_SPARE				0x100
+
+#define EMC_FBIO_CFG6				0x114
+#define EMC_EMRS2				0x12c
+#define EMC_MRW2				0x134
+#define EMC_MRW4				0x13c
+#define EMC_EINPUT				0x14c
+#define EMC_EINPUT_DURATION			0x150
+#define EMC_PUTERM_EXTRA			0x154
+#define EMC_TCKESR				0x158
+#define EMC_TPD					0x15c
+
+#define EMC_AUTO_CAL_CONFIG			0x2a4
+#define EMC_AUTO_CAL_CONFIG_AUTO_CAL_START	BIT(31)
+#define EMC_AUTO_CAL_INTERVAL			0x2a8
+#define EMC_AUTO_CAL_STATUS			0x2ac
+#define EMC_AUTO_CAL_STATUS_ACTIVE		BIT(31)
+#define EMC_STATUS				0x2b4
+#define EMC_STATUS_TIMING_UPDATE_STALLED	BIT(23)
+
+#define EMC_CFG_2				0x2b8
+#define EMC_CFG_2_MODE_SHIFT			0
+#define EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR	BIT(6)
+
+#define EMC_CFG_DIG_DLL				0x2bc
+#define EMC_CFG_DIG_DLL_PERIOD			0x2c0
+#define EMC_RDV_MASK				0x2cc
+#define EMC_WDV_MASK				0x2d0
+#define EMC_CTT_DURATION			0x2d8
+#define EMC_CTT_TERM_CTRL			0x2dc
+#define EMC_ZCAL_INTERVAL			0x2e0
+#define EMC_ZCAL_WAIT_CNT			0x2e4
+
+#define EMC_ZQ_CAL				0x2ec
+#define EMC_ZQ_CAL_CMD				BIT(0)
+#define EMC_ZQ_CAL_LONG				BIT(4)
+#define EMC_ZQ_CAL_LONG_CMD_DEV0		\
+	(DRAM_DEV_SEL_0 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
+#define EMC_ZQ_CAL_LONG_CMD_DEV1		\
+	(DRAM_DEV_SEL_1 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
+
+#define EMC_XM2CMDPADCTRL			0x2f0
+#define EMC_XM2DQSPADCTRL			0x2f8
+#define EMC_XM2DQSPADCTRL2			0x2fc
+#define EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE	BIT(0)
+#define EMC_XM2DQSPADCTRL2_VREF_ENABLE		BIT(5)
+#define EMC_XM2DQPADCTRL			0x300
+#define EMC_XM2DQPADCTRL2			0x304
+#define EMC_XM2CLKPADCTRL			0x308
+#define EMC_XM2COMPPADCTRL			0x30c
+#define EMC_XM2VTTGENPADCTRL			0x310
+#define EMC_XM2VTTGENPADCTRL2			0x314
+#define EMC_XM2VTTGENPADCTRL3			0x318
+#define EMC_XM2DQSPADCTRL4			0x320
+#define EMC_DLL_XFORM_DQS0			0x328
+#define EMC_DLL_XFORM_DQS1			0x32c
+#define EMC_DLL_XFORM_DQS2			0x330
+#define EMC_DLL_XFORM_DQS3			0x334
+#define EMC_DLL_XFORM_DQS4			0x338
+#define EMC_DLL_XFORM_DQS5			0x33c
+#define EMC_DLL_XFORM_DQS6			0x340
+#define EMC_DLL_XFORM_DQS7			0x344
+#define EMC_DLL_XFORM_QUSE0			0x348
+#define EMC_DLL_XFORM_QUSE1			0x34c
+#define EMC_DLL_XFORM_QUSE2			0x350
+#define EMC_DLL_XFORM_QUSE3			0x354
+#define EMC_DLL_XFORM_QUSE4			0x358
+#define EMC_DLL_XFORM_QUSE5			0x35c
+#define EMC_DLL_XFORM_QUSE6			0x360
+#define EMC_DLL_XFORM_QUSE7			0x364
+#define EMC_DLL_XFORM_DQ0			0x368
+#define EMC_DLL_XFORM_DQ1			0x36c
+#define EMC_DLL_XFORM_DQ2			0x370
+#define EMC_DLL_XFORM_DQ3			0x374
+#define EMC_DLI_TRIM_TXDQS0			0x3a8
+#define EMC_DLI_TRIM_TXDQS1			0x3ac
+#define EMC_DLI_TRIM_TXDQS2			0x3b0
+#define EMC_DLI_TRIM_TXDQS3			0x3b4
+#define EMC_DLI_TRIM_TXDQS4			0x3b8
+#define EMC_DLI_TRIM_TXDQS5			0x3bc
+#define EMC_DLI_TRIM_TXDQS6			0x3c0
+#define EMC_DLI_TRIM_TXDQS7			0x3c4
+#define EMC_STALL_THEN_EXE_AFTER_CLKCHANGE	0x3cc
+#define EMC_SEL_DPD_CTRL			0x3d8
+#define EMC_SEL_DPD_CTRL_DATA_SEL_DPD		BIT(8)
+#define EMC_SEL_DPD_CTRL_ODT_SEL_DPD		BIT(5)
+#define EMC_SEL_DPD_CTRL_RESET_SEL_DPD		BIT(4)
+#define EMC_SEL_DPD_CTRL_CA_SEL_DPD		BIT(3)
+#define EMC_SEL_DPD_CTRL_CLK_SEL_DPD		BIT(2)
+#define EMC_SEL_DPD_CTRL_DDR3_MASK	\
+	((0xf << 2) | BIT(8))
+#define EMC_SEL_DPD_CTRL_MASK \
+	((0x3 << 2) | BIT(5) | BIT(8))
+#define EMC_PRE_REFRESH_REQ_CNT			0x3dc
+#define EMC_DYN_SELF_REF_CONTROL		0x3e0
+#define EMC_TXSRDLL				0x3e4
+#define EMC_CCFIFO_ADDR				0x3e8
+#define EMC_CCFIFO_DATA				0x3ec
+#define EMC_CCFIFO_STATUS			0x3f0
+#define EMC_CDB_CNTL_1				0x3f4
+#define EMC_CDB_CNTL_2				0x3f8
+#define EMC_XM2CLKPADCTRL2			0x3fc
+#define EMC_AUTO_CAL_CONFIG2			0x458
+#define EMC_AUTO_CAL_CONFIG3			0x45c
+#define EMC_IBDLY				0x468
+#define EMC_DLL_XFORM_ADDR0			0x46c
+#define EMC_DLL_XFORM_ADDR1			0x470
+#define EMC_DLL_XFORM_ADDR2			0x474
+#define EMC_DSR_VTTGEN_DRV			0x47c
+#define EMC_TXDSRVTTGEN				0x480
+#define EMC_XM2CMDPADCTRL4			0x484
+#define EMC_XM2CMDPADCTRL5			0x488
+#define EMC_DLL_XFORM_DQS8			0x4a0
+#define EMC_DLL_XFORM_DQS9			0x4a4
+#define EMC_DLL_XFORM_DQS10			0x4a8
+#define EMC_DLL_XFORM_DQS11			0x4ac
+#define EMC_DLL_XFORM_DQS12			0x4b0
+#define EMC_DLL_XFORM_DQS13			0x4b4
+#define EMC_DLL_XFORM_DQS14			0x4b8
+#define EMC_DLL_XFORM_DQS15			0x4bc
+#define EMC_DLL_XFORM_QUSE8			0x4c0
+#define EMC_DLL_XFORM_QUSE9			0x4c4
+#define EMC_DLL_XFORM_QUSE10			0x4c8
+#define EMC_DLL_XFORM_QUSE11			0x4cc
+#define EMC_DLL_XFORM_QUSE12			0x4d0
+#define EMC_DLL_XFORM_QUSE13			0x4d4
+#define EMC_DLL_XFORM_QUSE14			0x4d8
+#define EMC_DLL_XFORM_QUSE15			0x4dc
+#define EMC_DLL_XFORM_DQ4			0x4e0
+#define EMC_DLL_XFORM_DQ5			0x4e4
+#define EMC_DLL_XFORM_DQ6			0x4e8
+#define EMC_DLL_XFORM_DQ7			0x4ec
+#define EMC_DLI_TRIM_TXDQS8			0x520
+#define EMC_DLI_TRIM_TXDQS9			0x524
+#define EMC_DLI_TRIM_TXDQS10			0x528
+#define EMC_DLI_TRIM_TXDQS11			0x52c
+#define EMC_DLI_TRIM_TXDQS12			0x530
+#define EMC_DLI_TRIM_TXDQS13			0x534
+#define EMC_DLI_TRIM_TXDQS14			0x538
+#define EMC_DLI_TRIM_TXDQS15			0x53c
+#define EMC_CDB_CNTL_3				0x540
+#define EMC_XM2DQSPADCTRL5			0x544
+#define EMC_XM2DQSPADCTRL6			0x548
+#define EMC_XM2DQPADCTRL3			0x54c
+#define EMC_DLL_XFORM_ADDR3			0x550
+#define EMC_DLL_XFORM_ADDR4			0x554
+#define EMC_DLL_XFORM_ADDR5			0x558
+#define EMC_CFG_PIPE				0x560
+#define EMC_QPOP				0x564
+#define EMC_QUSE_WIDTH				0x568
+#define EMC_PUTERM_WIDTH			0x56c
+#define EMC_BGBIAS_CTL0				0x570
+#define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX BIT(3)
+#define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN BIT(2)
+#define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD	BIT(1)
+#define EMC_PUTERM_ADJ				0x574
+
+#define DRAM_DEV_SEL_ALL			0
+#define DRAM_DEV_SEL_0				BIT(31)
+#define DRAM_DEV_SEL_1				BIT(30)
+
+#define EMC_CFG_POWER_FEATURES_MASK		\
+	(EMC_CFG_DYN_SREF | EMC_CFG_DRAM_ACPD | EMC_CFG_DRAM_CLKSTOP_SR | \
+	EMC_CFG_DRAM_CLKSTOP_PD | EMC_CFG_DSR_VTTGEN_DRV_EN)
+#define EMC_REFCTRL_DEV_SEL(n) (((n > 1) ? 0 : 2) << EMC_REFCTRL_DEV_SEL_SHIFT)
+#define EMC_DRAM_DEV_SEL(n) ((n > 1) ? DRAM_DEV_SEL_ALL : DRAM_DEV_SEL_0)
+
+/* Maximum amount of time in us. to wait for changes to become effective */
+#define EMC_STATUS_UPDATE_TIMEOUT		1000
+
+enum emc_dram_type {
+	DRAM_TYPE_DDR3 = 0,
+	DRAM_TYPE_DDR1 = 1,
+	DRAM_TYPE_LPDDR3 = 2,
+	DRAM_TYPE_DDR2 = 3
+};
+
+enum emc_dll_change {
+	DLL_CHANGE_NONE,
+	DLL_CHANGE_ON,
+	DLL_CHANGE_OFF
+};
+
+static const unsigned long emc_burst_regs[] = {
+	EMC_RC,
+	EMC_RFC,
+	EMC_RFC_SLR,
+	EMC_RAS,
+	EMC_RP,
+	EMC_R2W,
+	EMC_W2R,
+	EMC_R2P,
+	EMC_W2P,
+	EMC_RD_RCD,
+	EMC_WR_RCD,
+	EMC_RRD,
+	EMC_REXT,
+	EMC_WEXT,
+	EMC_WDV,
+	EMC_WDV_MASK,
+	EMC_QUSE,
+	EMC_QUSE_WIDTH,
+	EMC_IBDLY,
+	EMC_EINPUT,
+	EMC_EINPUT_DURATION,
+	EMC_PUTERM_EXTRA,
+	EMC_PUTERM_WIDTH,
+	EMC_PUTERM_ADJ,
+	EMC_CDB_CNTL_1,
+	EMC_CDB_CNTL_2,
+	EMC_CDB_CNTL_3,
+	EMC_QRST,
+	EMC_QSAFE,
+	EMC_RDV,
+	EMC_RDV_MASK,
+	EMC_REFRESH,
+	EMC_BURST_REFRESH_NUM,
+	EMC_PRE_REFRESH_REQ_CNT,
+	EMC_PDEX2WR,
+	EMC_PDEX2RD,
+	EMC_PCHG2PDEN,
+	EMC_ACT2PDEN,
+	EMC_AR2PDEN,
+	EMC_RW2PDEN,
+	EMC_TXSR,
+	EMC_TXSRDLL,
+	EMC_TCKE,
+	EMC_TCKESR,
+	EMC_TPD,
+	EMC_TFAW,
+	EMC_TRPAB,
+	EMC_TCLKSTABLE,
+	EMC_TCLKSTOP,
+	EMC_TREFBW,
+	EMC_FBIO_CFG6,
+	EMC_ODT_WRITE,
+	EMC_ODT_READ,
+	EMC_FBIO_CFG5,
+	EMC_CFG_DIG_DLL,
+	EMC_CFG_DIG_DLL_PERIOD,
+	EMC_DLL_XFORM_DQS0,
+	EMC_DLL_XFORM_DQS1,
+	EMC_DLL_XFORM_DQS2,
+	EMC_DLL_XFORM_DQS3,
+	EMC_DLL_XFORM_DQS4,
+	EMC_DLL_XFORM_DQS5,
+	EMC_DLL_XFORM_DQS6,
+	EMC_DLL_XFORM_DQS7,
+	EMC_DLL_XFORM_DQS8,
+	EMC_DLL_XFORM_DQS9,
+	EMC_DLL_XFORM_DQS10,
+	EMC_DLL_XFORM_DQS11,
+	EMC_DLL_XFORM_DQS12,
+	EMC_DLL_XFORM_DQS13,
+	EMC_DLL_XFORM_DQS14,
+	EMC_DLL_XFORM_DQS15,
+	EMC_DLL_XFORM_QUSE0,
+	EMC_DLL_XFORM_QUSE1,
+	EMC_DLL_XFORM_QUSE2,
+	EMC_DLL_XFORM_QUSE3,
+	EMC_DLL_XFORM_QUSE4,
+	EMC_DLL_XFORM_QUSE5,
+	EMC_DLL_XFORM_QUSE6,
+	EMC_DLL_XFORM_QUSE7,
+	EMC_DLL_XFORM_ADDR0,
+	EMC_DLL_XFORM_ADDR1,
+	EMC_DLL_XFORM_ADDR2,
+	EMC_DLL_XFORM_ADDR3,
+	EMC_DLL_XFORM_ADDR4,
+	EMC_DLL_XFORM_ADDR5,
+	EMC_DLL_XFORM_QUSE8,
+	EMC_DLL_XFORM_QUSE9,
+	EMC_DLL_XFORM_QUSE10,
+	EMC_DLL_XFORM_QUSE11,
+	EMC_DLL_XFORM_QUSE12,
+	EMC_DLL_XFORM_QUSE13,
+	EMC_DLL_XFORM_QUSE14,
+	EMC_DLL_XFORM_QUSE15,
+	EMC_DLI_TRIM_TXDQS0,
+	EMC_DLI_TRIM_TXDQS1,
+	EMC_DLI_TRIM_TXDQS2,
+	EMC_DLI_TRIM_TXDQS3,
+	EMC_DLI_TRIM_TXDQS4,
+	EMC_DLI_TRIM_TXDQS5,
+	EMC_DLI_TRIM_TXDQS6,
+	EMC_DLI_TRIM_TXDQS7,
+	EMC_DLI_TRIM_TXDQS8,
+	EMC_DLI_TRIM_TXDQS9,
+	EMC_DLI_TRIM_TXDQS10,
+	EMC_DLI_TRIM_TXDQS11,
+	EMC_DLI_TRIM_TXDQS12,
+	EMC_DLI_TRIM_TXDQS13,
+	EMC_DLI_TRIM_TXDQS14,
+	EMC_DLI_TRIM_TXDQS15,
+	EMC_DLL_XFORM_DQ0,
+	EMC_DLL_XFORM_DQ1,
+	EMC_DLL_XFORM_DQ2,
+	EMC_DLL_XFORM_DQ3,
+	EMC_DLL_XFORM_DQ4,
+	EMC_DLL_XFORM_DQ5,
+	EMC_DLL_XFORM_DQ6,
+	EMC_DLL_XFORM_DQ7,
+	EMC_XM2CMDPADCTRL,
+	EMC_XM2CMDPADCTRL4,
+	EMC_XM2CMDPADCTRL5,
+	EMC_XM2DQPADCTRL2,
+	EMC_XM2DQPADCTRL3,
+	EMC_XM2CLKPADCTRL,
+	EMC_XM2CLKPADCTRL2,
+	EMC_XM2COMPPADCTRL,
+	EMC_XM2VTTGENPADCTRL,
+	EMC_XM2VTTGENPADCTRL2,
+	EMC_XM2VTTGENPADCTRL3,
+	EMC_XM2DQSPADCTRL3,
+	EMC_XM2DQSPADCTRL4,
+	EMC_XM2DQSPADCTRL5,
+	EMC_XM2DQSPADCTRL6,
+	EMC_DSR_VTTGEN_DRV,
+	EMC_TXDSRVTTGEN,
+	EMC_FBIO_SPARE,
+	EMC_ZCAL_WAIT_CNT,
+	EMC_MRS_WAIT_CNT2,
+	EMC_CTT,
+	EMC_CTT_DURATION,
+	EMC_CFG_PIPE,
+	EMC_DYN_SELF_REF_CONTROL,
+	EMC_QPOP
+};
+
+struct emc_timing {
+	unsigned long rate;
+
+	u32 emc_burst_data[ARRAY_SIZE(emc_burst_regs)];
+
+	u32 emc_auto_cal_config;
+	u32 emc_auto_cal_config2;
+	u32 emc_auto_cal_config3;
+	u32 emc_auto_cal_interval;
+	u32 emc_bgbias_ctl0;
+	u32 emc_cfg;
+	u32 emc_cfg_2;
+	u32 emc_ctt_term_ctrl;
+	u32 emc_mode_1;
+	u32 emc_mode_2;
+	u32 emc_mode_4;
+	u32 emc_mode_reset;
+	u32 emc_mrs_wait_cnt;
+	u32 emc_sel_dpd_ctrl;
+	u32 emc_xm2dqspadctrl2;
+	u32 emc_zcal_cnt_long;
+	u32 emc_zcal_interval;
+};
+
+enum emc_rate_request_type {
+	EMC_RATE_DEBUG,
+	EMC_RATE_ICC,
+	EMC_RATE_TYPE_MAX,
+};
+
+struct emc_rate_request {
+	unsigned long min_rate;
+	unsigned long max_rate;
+};
+
+struct tegra_emc {
+	struct device *dev;
+
+	struct tegra_mc *mc;
+
+	void __iomem *regs;
+
+	struct clk *clk;
+
+	enum emc_dram_type dram_type;
+	unsigned int dram_bus_width;
+	unsigned int dram_num;
+
+	struct emc_timing last_timing;
+	struct emc_timing *timings;
+	unsigned int num_timings;
+
+	struct {
+		struct dentry *root;
+		unsigned long min_rate;
+		unsigned long max_rate;
+	} debugfs;
+
+	struct icc_provider provider;
+
+	/*
+	 * There are multiple sources in the EMC driver which could request
+	 * a min/max clock rate, these rates are contained in this array.
+	 */
+	struct emc_rate_request requested_rate[EMC_RATE_TYPE_MAX];
+
+	/* protect shared rate-change code path */
+	struct mutex rate_lock;
+};
+
+/* Timing change sequence functions */
+
+static void emc_ccfifo_writel(struct tegra_emc *emc, u32 value,
+			      unsigned long offset)
+{
+	writel(value, emc->regs + EMC_CCFIFO_DATA);
+	writel(offset, emc->regs + EMC_CCFIFO_ADDR);
+}
+
+static void emc_seq_update_timing(struct tegra_emc *emc)
+{
+	unsigned int i;
+	u32 value;
+
+	writel(1, emc->regs + EMC_TIMING_CONTROL);
+
+	for (i = 0; i < EMC_STATUS_UPDATE_TIMEOUT; ++i) {
+		value = readl(emc->regs + EMC_STATUS);
+		if ((value & EMC_STATUS_TIMING_UPDATE_STALLED) == 0)
+			return;
+		udelay(1);
+	}
+
+	dev_err(emc->dev, "timing update timed out\n");
+}
+
+static void emc_seq_disable_auto_cal(struct tegra_emc *emc)
+{
+	unsigned int i;
+	u32 value;
+
+	writel(0, emc->regs + EMC_AUTO_CAL_INTERVAL);
+
+	for (i = 0; i < EMC_STATUS_UPDATE_TIMEOUT; ++i) {
+		value = readl(emc->regs + EMC_AUTO_CAL_STATUS);
+		if ((value & EMC_AUTO_CAL_STATUS_ACTIVE) == 0)
+			return;
+		udelay(1);
+	}
+
+	dev_err(emc->dev, "auto cal disable timed out\n");
+}
+
+static void emc_seq_wait_clkchange(struct tegra_emc *emc)
+{
+	unsigned int i;
+	u32 value;
+
+	for (i = 0; i < EMC_STATUS_UPDATE_TIMEOUT; ++i) {
+		value = readl(emc->regs + EMC_INTSTATUS);
+		if (value & EMC_INTSTATUS_CLKCHANGE_COMPLETE)
+			return;
+		udelay(1);
+	}
+
+	dev_err(emc->dev, "clock change timed out\n");
+}
+
+static struct emc_timing *tegra_emc_find_timing(struct tegra_emc *emc,
+						unsigned long rate)
+{
+	struct emc_timing *timing = NULL;
+	unsigned int i;
+
+	for (i = 0; i < emc->num_timings; i++) {
+		if (emc->timings[i].rate == rate) {
+			timing = &emc->timings[i];
+			break;
+		}
+	}
+
+	if (!timing) {
+		dev_err(emc->dev, "no timing for rate %lu\n", rate);
+		return NULL;
+	}
+
+	return timing;
+}
+
+static int tegra_emc_prepare_timing_change(struct tegra_emc *emc,
+					   unsigned long rate)
+{
+	struct emc_timing *timing = tegra_emc_find_timing(emc, rate);
+	struct emc_timing *last = &emc->last_timing;
+	enum emc_dll_change dll_change;
+	unsigned int pre_wait = 0;
+	u32 val, val2, mask;
+	bool update = false;
+	unsigned int i;
+
+	if (!timing)
+		return -ENOENT;
+
+	if ((last->emc_mode_1 & 0x1) == (timing->emc_mode_1 & 0x1))
+		dll_change = DLL_CHANGE_NONE;
+	else if (timing->emc_mode_1 & 0x1)
+		dll_change = DLL_CHANGE_ON;
+	else
+		dll_change = DLL_CHANGE_OFF;
+
+	/* Clear CLKCHANGE_COMPLETE interrupts */
+	writel(EMC_INTSTATUS_CLKCHANGE_COMPLETE, emc->regs + EMC_INTSTATUS);
+
+	/* Disable dynamic self-refresh */
+	val = readl(emc->regs + EMC_CFG);
+	if (val & EMC_CFG_PWR_MASK) {
+		val &= ~EMC_CFG_POWER_FEATURES_MASK;
+		writel(val, emc->regs + EMC_CFG);
+
+		pre_wait = 5;
+	}
+
+	/* Disable SEL_DPD_CTRL for clock change */
+	if (emc->dram_type == DRAM_TYPE_DDR3)
+		mask = EMC_SEL_DPD_CTRL_DDR3_MASK;
+	else
+		mask = EMC_SEL_DPD_CTRL_MASK;
+
+	val = readl(emc->regs + EMC_SEL_DPD_CTRL);
+	if (val & mask) {
+		val &= ~mask;
+		writel(val, emc->regs + EMC_SEL_DPD_CTRL);
+	}
+
+	/* Prepare DQ/DQS for clock change */
+	val = readl(emc->regs + EMC_BGBIAS_CTL0);
+	val2 = last->emc_bgbias_ctl0;
+	if (!(timing->emc_bgbias_ctl0 &
+	      EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX) &&
+	    (val & EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX)) {
+		val2 &= ~EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX;
+		update = true;
+	}
+
+	if ((val & EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD) ||
+	    (val & EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN)) {
+		update = true;
+	}
+
+	if (update) {
+		writel(val2, emc->regs + EMC_BGBIAS_CTL0);
+		if (pre_wait < 5)
+			pre_wait = 5;
+	}
+
+	update = false;
+	val = readl(emc->regs + EMC_XM2DQSPADCTRL2);
+	if (timing->emc_xm2dqspadctrl2 & EMC_XM2DQSPADCTRL2_VREF_ENABLE &&
+	    !(val & EMC_XM2DQSPADCTRL2_VREF_ENABLE)) {
+		val |= EMC_XM2DQSPADCTRL2_VREF_ENABLE;
+		update = true;
+	}
+
+	if (timing->emc_xm2dqspadctrl2 & EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE &&
+	    !(val & EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE)) {
+		val |= EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE;
+		update = true;
+	}
+
+	if (update) {
+		writel(val, emc->regs + EMC_XM2DQSPADCTRL2);
+		if (pre_wait < 30)
+			pre_wait = 30;
+	}
+
+	/* Wait to settle */
+	if (pre_wait) {
+		emc_seq_update_timing(emc);
+		udelay(pre_wait);
+	}
+
+	/* Program CTT_TERM control */
+	if (last->emc_ctt_term_ctrl != timing->emc_ctt_term_ctrl) {
+		emc_seq_disable_auto_cal(emc);
+		writel(timing->emc_ctt_term_ctrl,
+		       emc->regs + EMC_CTT_TERM_CTRL);
+		emc_seq_update_timing(emc);
+	}
+
+	/* Program burst shadow registers */
+	for (i = 0; i < ARRAY_SIZE(timing->emc_burst_data); ++i)
+		writel(timing->emc_burst_data[i],
+		       emc->regs + emc_burst_regs[i]);
+
+	writel(timing->emc_xm2dqspadctrl2, emc->regs + EMC_XM2DQSPADCTRL2);
+	writel(timing->emc_zcal_interval, emc->regs + EMC_ZCAL_INTERVAL);
+
+	tegra_mc_write_emem_configuration(emc->mc, timing->rate);
+
+	val = timing->emc_cfg & ~EMC_CFG_POWER_FEATURES_MASK;
+	emc_ccfifo_writel(emc, val, EMC_CFG);
+
+	/* Program AUTO_CAL_CONFIG */
+	if (timing->emc_auto_cal_config2 != last->emc_auto_cal_config2)
+		emc_ccfifo_writel(emc, timing->emc_auto_cal_config2,
+				  EMC_AUTO_CAL_CONFIG2);
+
+	if (timing->emc_auto_cal_config3 != last->emc_auto_cal_config3)
+		emc_ccfifo_writel(emc, timing->emc_auto_cal_config3,
+				  EMC_AUTO_CAL_CONFIG3);
+
+	if (timing->emc_auto_cal_config != last->emc_auto_cal_config) {
+		val = timing->emc_auto_cal_config;
+		val &= EMC_AUTO_CAL_CONFIG_AUTO_CAL_START;
+		emc_ccfifo_writel(emc, val, EMC_AUTO_CAL_CONFIG);
+	}
+
+	/* DDR3: predict MRS long wait count */
+	if (emc->dram_type == DRAM_TYPE_DDR3 &&
+	    dll_change == DLL_CHANGE_ON) {
+		u32 cnt = 512;
+
+		if (timing->emc_zcal_interval != 0 &&
+		    last->emc_zcal_interval == 0)
+			cnt -= emc->dram_num * 256;
+
+		val = (timing->emc_mrs_wait_cnt
+			& EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK)
+			>> EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT;
+		if (cnt < val)
+			cnt = val;
+
+		val = timing->emc_mrs_wait_cnt
+			& ~EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
+		val |= (cnt << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
+			& EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
+
+		writel(val, emc->regs + EMC_MRS_WAIT_CNT);
+	}
+
+	val = timing->emc_cfg_2;
+	val &= ~EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR;
+	emc_ccfifo_writel(emc, val, EMC_CFG_2);
+
+	/* DDR3: Turn off DLL and enter self-refresh */
+	if (emc->dram_type == DRAM_TYPE_DDR3 && dll_change == DLL_CHANGE_OFF)
+		emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_EMRS);
+
+	/* Disable refresh controller */
+	emc_ccfifo_writel(emc, EMC_REFCTRL_DEV_SEL(emc->dram_num),
+			  EMC_REFCTRL);
+	if (emc->dram_type == DRAM_TYPE_DDR3)
+		emc_ccfifo_writel(emc, EMC_DRAM_DEV_SEL(emc->dram_num) |
+				       EMC_SELF_REF_CMD_ENABLED,
+				  EMC_SELF_REF);
+
+	/* Flow control marker */
+	emc_ccfifo_writel(emc, 1, EMC_STALL_THEN_EXE_AFTER_CLKCHANGE);
+
+	/* DDR3: Exit self-refresh */
+	if (emc->dram_type == DRAM_TYPE_DDR3)
+		emc_ccfifo_writel(emc, EMC_DRAM_DEV_SEL(emc->dram_num),
+				  EMC_SELF_REF);
+	emc_ccfifo_writel(emc, EMC_REFCTRL_DEV_SEL(emc->dram_num) |
+			       EMC_REFCTRL_ENABLE,
+			  EMC_REFCTRL);
+
+	/* Set DRAM mode registers */
+	if (emc->dram_type == DRAM_TYPE_DDR3) {
+		if (timing->emc_mode_1 != last->emc_mode_1)
+			emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_EMRS);
+		if (timing->emc_mode_2 != last->emc_mode_2)
+			emc_ccfifo_writel(emc, timing->emc_mode_2, EMC_EMRS2);
+
+		if ((timing->emc_mode_reset != last->emc_mode_reset) ||
+		    dll_change == DLL_CHANGE_ON) {
+			val = timing->emc_mode_reset;
+			if (dll_change == DLL_CHANGE_ON) {
+				val |= EMC_MODE_SET_DLL_RESET;
+				val |= EMC_MODE_SET_LONG_CNT;
+			} else {
+				val &= ~EMC_MODE_SET_DLL_RESET;
+			}
+			emc_ccfifo_writel(emc, val, EMC_MRS);
+		}
+	} else {
+		if (timing->emc_mode_2 != last->emc_mode_2)
+			emc_ccfifo_writel(emc, timing->emc_mode_2, EMC_MRW2);
+		if (timing->emc_mode_1 != last->emc_mode_1)
+			emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_MRW);
+		if (timing->emc_mode_4 != last->emc_mode_4)
+			emc_ccfifo_writel(emc, timing->emc_mode_4, EMC_MRW4);
+	}
+
+	/*  Issue ZCAL command if turning ZCAL on */
+	if (timing->emc_zcal_interval != 0 && last->emc_zcal_interval == 0) {
+		emc_ccfifo_writel(emc, EMC_ZQ_CAL_LONG_CMD_DEV0, EMC_ZQ_CAL);
+		if (emc->dram_num > 1)
+			emc_ccfifo_writel(emc, EMC_ZQ_CAL_LONG_CMD_DEV1,
+					  EMC_ZQ_CAL);
+	}
+
+	/*  Write to RO register to remove stall after change */
+	emc_ccfifo_writel(emc, 0, EMC_CCFIFO_STATUS);
+
+	if (timing->emc_cfg_2 & EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR)
+		emc_ccfifo_writel(emc, timing->emc_cfg_2, EMC_CFG_2);
+
+	/* Disable AUTO_CAL for clock change */
+	emc_seq_disable_auto_cal(emc);
+
+	/* Read register to wait until programming has settled */
+	readl(emc->regs + EMC_INTSTATUS);
+
+	return 0;
+}
+
+static void tegra_emc_complete_timing_change(struct tegra_emc *emc,
+					     unsigned long rate)
+{
+	struct emc_timing *timing = tegra_emc_find_timing(emc, rate);
+	struct emc_timing *last = &emc->last_timing;
+	u32 val;
+
+	if (!timing)
+		return;
+
+	/* Wait until the state machine has settled */
+	emc_seq_wait_clkchange(emc);
+
+	/* Restore AUTO_CAL */
+	if (timing->emc_ctt_term_ctrl != last->emc_ctt_term_ctrl)
+		writel(timing->emc_auto_cal_interval,
+		       emc->regs + EMC_AUTO_CAL_INTERVAL);
+
+	/* Restore dynamic self-refresh */
+	if (timing->emc_cfg & EMC_CFG_PWR_MASK)
+		writel(timing->emc_cfg, emc->regs + EMC_CFG);
+
+	/* Set ZCAL wait count */
+	writel(timing->emc_zcal_cnt_long, emc->regs + EMC_ZCAL_WAIT_CNT);
+
+	/* LPDDR3: Turn off BGBIAS if low frequency */
+	if (emc->dram_type == DRAM_TYPE_LPDDR3 &&
+	    timing->emc_bgbias_ctl0 &
+	      EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX) {
+		val = timing->emc_bgbias_ctl0;
+		val |= EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN;
+		val |= EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD;
+		writel(val, emc->regs + EMC_BGBIAS_CTL0);
+	} else {
+		if (emc->dram_type == DRAM_TYPE_DDR3 &&
+		    readl(emc->regs + EMC_BGBIAS_CTL0) !=
+		      timing->emc_bgbias_ctl0) {
+			writel(timing->emc_bgbias_ctl0,
+			       emc->regs + EMC_BGBIAS_CTL0);
+		}
+
+		writel(timing->emc_auto_cal_interval,
+		       emc->regs + EMC_AUTO_CAL_INTERVAL);
+	}
+
+	/* Wait for timing to settle */
+	udelay(2);
+
+	/* Reprogram SEL_DPD_CTRL */
+	writel(timing->emc_sel_dpd_ctrl, emc->regs + EMC_SEL_DPD_CTRL);
+	emc_seq_update_timing(emc);
+
+	emc->last_timing = *timing;
+}
+
+/* Initialization and deinitialization */
+
+static void emc_read_current_timing(struct tegra_emc *emc,
+				    struct emc_timing *timing)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(emc_burst_regs); ++i)
+		timing->emc_burst_data[i] =
+			readl(emc->regs + emc_burst_regs[i]);
+
+	timing->emc_cfg = readl(emc->regs + EMC_CFG);
+
+	timing->emc_auto_cal_interval = 0;
+	timing->emc_zcal_cnt_long = 0;
+	timing->emc_mode_1 = 0;
+	timing->emc_mode_2 = 0;
+	timing->emc_mode_4 = 0;
+	timing->emc_mode_reset = 0;
+}
+
+static int emc_init(struct tegra_emc *emc)
+{
+	emc->dram_type = readl(emc->regs + EMC_FBIO_CFG5);
+
+	if (emc->dram_type & EMC_FBIO_CFG5_DRAM_WIDTH_X64)
+		emc->dram_bus_width = 64;
+	else
+		emc->dram_bus_width = 32;
+
+	dev_info_once(emc->dev, "%ubit DRAM bus\n", emc->dram_bus_width);
+
+	emc->dram_type &= EMC_FBIO_CFG5_DRAM_TYPE_MASK;
+	emc->dram_type >>= EMC_FBIO_CFG5_DRAM_TYPE_SHIFT;
+
+	emc->dram_num = tegra_mc_get_emem_device_count(emc->mc);
+
+	emc_read_current_timing(emc, &emc->last_timing);
+
+	return 0;
+}
+
+static int load_one_timing_from_dt(struct tegra_emc *emc,
+				   struct emc_timing *timing,
+				   struct device_node *node)
+{
+	u32 value;
+	int err;
+
+	err = of_property_read_u32(node, "clock-frequency", &value);
+	if (err) {
+		dev_err(emc->dev, "timing %pOFn: failed to read rate: %d\n",
+			node, err);
+		return err;
+	}
+
+	timing->rate = value;
+
+	err = of_property_read_u32_array(node, "nvidia,emc-configuration",
+					 timing->emc_burst_data,
+					 ARRAY_SIZE(timing->emc_burst_data));
+	if (err) {
+		dev_err(emc->dev,
+			"timing %pOFn: failed to read emc burst data: %d\n",
+			node, err);
+		return err;
+	}
+
+#define EMC_READ_PROP(prop, dtprop) { \
+	err = of_property_read_u32(node, dtprop, &timing->prop); \
+	if (err) { \
+		dev_err(emc->dev, "timing %pOFn: failed to read " #prop ": %d\n", \
+			node, err); \
+		return err; \
+	} \
+}
+
+	EMC_READ_PROP(emc_auto_cal_config, "nvidia,emc-auto-cal-config")
+	EMC_READ_PROP(emc_auto_cal_config2, "nvidia,emc-auto-cal-config2")
+	EMC_READ_PROP(emc_auto_cal_config3, "nvidia,emc-auto-cal-config3")
+	EMC_READ_PROP(emc_auto_cal_interval, "nvidia,emc-auto-cal-interval")
+	EMC_READ_PROP(emc_bgbias_ctl0, "nvidia,emc-bgbias-ctl0")
+	EMC_READ_PROP(emc_cfg, "nvidia,emc-cfg")
+	EMC_READ_PROP(emc_cfg_2, "nvidia,emc-cfg-2")
+	EMC_READ_PROP(emc_ctt_term_ctrl, "nvidia,emc-ctt-term-ctrl")
+	EMC_READ_PROP(emc_mode_1, "nvidia,emc-mode-1")
+	EMC_READ_PROP(emc_mode_2, "nvidia,emc-mode-2")
+	EMC_READ_PROP(emc_mode_4, "nvidia,emc-mode-4")
+	EMC_READ_PROP(emc_mode_reset, "nvidia,emc-mode-reset")
+	EMC_READ_PROP(emc_mrs_wait_cnt, "nvidia,emc-mrs-wait-cnt")
+	EMC_READ_PROP(emc_sel_dpd_ctrl, "nvidia,emc-sel-dpd-ctrl")
+	EMC_READ_PROP(emc_xm2dqspadctrl2, "nvidia,emc-xm2dqspadctrl2")
+	EMC_READ_PROP(emc_zcal_cnt_long, "nvidia,emc-zcal-cnt-long")
+	EMC_READ_PROP(emc_zcal_interval, "nvidia,emc-zcal-interval")
+
+#undef EMC_READ_PROP
+
+	return 0;
+}
+
+static int cmp_timings(const void *_a, const void *_b)
+{
+	const struct emc_timing *a = _a;
+	const struct emc_timing *b = _b;
+
+	if (a->rate < b->rate)
+		return -1;
+	else if (a->rate == b->rate)
+		return 0;
+	else
+		return 1;
+}
+
+static int tegra_emc_load_timings_from_dt(struct tegra_emc *emc,
+					  struct device_node *node)
+{
+	int child_count = of_get_child_count(node);
+	struct device_node *child;
+	struct emc_timing *timing;
+	unsigned int i = 0;
+	int err;
+
+	emc->timings = devm_kcalloc(emc->dev, child_count, sizeof(*timing),
+				    GFP_KERNEL);
+	if (!emc->timings)
+		return -ENOMEM;
+
+	emc->num_timings = child_count;
+
+	for_each_child_of_node(node, child) {
+		timing = &emc->timings[i++];
+
+		err = load_one_timing_from_dt(emc, timing, child);
+		if (err) {
+			of_node_put(child);
+			return err;
+		}
+	}
+
+	sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings,
+	     NULL);
+
+	return 0;
+}
+
+static const struct of_device_id tegra_emc_of_match[] = {
+	{ .compatible = "nvidia,tegra124-emc" },
+	{ .compatible = "nvidia,tegra132-emc" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, tegra_emc_of_match);
+
+static struct device_node *
+tegra_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code)
+{
+	struct device_node *np;
+	int err;
+
+	for_each_child_of_node(node, np) {
+		u32 value;
+
+		err = of_property_read_u32(np, "nvidia,ram-code", &value);
+		if (err || (value != ram_code))
+			continue;
+
+		return np;
+	}
+
+	return NULL;
+}
+
+static void tegra_emc_rate_requests_init(struct tegra_emc *emc)
+{
+	unsigned int i;
+
+	for (i = 0; i < EMC_RATE_TYPE_MAX; i++) {
+		emc->requested_rate[i].min_rate = 0;
+		emc->requested_rate[i].max_rate = ULONG_MAX;
+	}
+}
+
+static int emc_request_rate(struct tegra_emc *emc,
+			    unsigned long new_min_rate,
+			    unsigned long new_max_rate,
+			    enum emc_rate_request_type type)
+{
+	struct emc_rate_request *req = emc->requested_rate;
+	unsigned long min_rate = 0, max_rate = ULONG_MAX;
+	unsigned int i;
+	int err;
+
+	/* select minimum and maximum rates among the requested rates */
+	for (i = 0; i < EMC_RATE_TYPE_MAX; i++, req++) {
+		if (i == type) {
+			min_rate = max(new_min_rate, min_rate);
+			max_rate = min(new_max_rate, max_rate);
+		} else {
+			min_rate = max(req->min_rate, min_rate);
+			max_rate = min(req->max_rate, max_rate);
+		}
+	}
+
+	if (min_rate > max_rate) {
+		dev_err_ratelimited(emc->dev, "%s: type %u: out of range: %lu %lu\n",
+				    __func__, type, min_rate, max_rate);
+		return -ERANGE;
+	}
+
+	/*
+	 * EMC rate-changes should go via OPP API because it manages voltage
+	 * changes.
+	 */
+	err = dev_pm_opp_set_rate(emc->dev, min_rate);
+	if (err)
+		return err;
+
+	emc->requested_rate[type].min_rate = new_min_rate;
+	emc->requested_rate[type].max_rate = new_max_rate;
+
+	return 0;
+}
+
+static int emc_set_min_rate(struct tegra_emc *emc, unsigned long rate,
+			    enum emc_rate_request_type type)
+{
+	struct emc_rate_request *req = &emc->requested_rate[type];
+	int ret;
+
+	mutex_lock(&emc->rate_lock);
+	ret = emc_request_rate(emc, rate, req->max_rate, type);
+	mutex_unlock(&emc->rate_lock);
+
+	return ret;
+}
+
+static int emc_set_max_rate(struct tegra_emc *emc, unsigned long rate,
+			    enum emc_rate_request_type type)
+{
+	struct emc_rate_request *req = &emc->requested_rate[type];
+	int ret;
+
+	mutex_lock(&emc->rate_lock);
+	ret = emc_request_rate(emc, req->min_rate, rate, type);
+	mutex_unlock(&emc->rate_lock);
+
+	return ret;
+}
+
+/*
+ * debugfs interface
+ *
+ * The memory controller driver exposes some files in debugfs that can be used
+ * to control the EMC frequency. The top-level directory can be found here:
+ *
+ *   /sys/kernel/debug/emc
+ *
+ * It contains the following files:
+ *
+ *   - available_rates: This file contains a list of valid, space-separated
+ *     EMC frequencies.
+ *
+ *   - min_rate: Writing a value to this file sets the given frequency as the
+ *       floor of the permitted range. If this is higher than the currently
+ *       configured EMC frequency, this will cause the frequency to be
+ *       increased so that it stays within the valid range.
+ *
+ *   - max_rate: Similarily to the min_rate file, writing a value to this file
+ *       sets the given frequency as the ceiling of the permitted range. If
+ *       the value is lower than the currently configured EMC frequency, this
+ *       will cause the frequency to be decreased so that it stays within the
+ *       valid range.
+ */
+
+static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
+{
+	unsigned int i;
+
+	for (i = 0; i < emc->num_timings; i++)
+		if (rate == emc->timings[i].rate)
+			return true;
+
+	return false;
+}
+
+static int tegra_emc_debug_available_rates_show(struct seq_file *s,
+						void *data)
+{
+	struct tegra_emc *emc = s->private;
+	const char *prefix = "";
+	unsigned int i;
+
+	for (i = 0; i < emc->num_timings; i++) {
+		seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
+		prefix = " ";
+	}
+
+	seq_puts(s, "\n");
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(tegra_emc_debug_available_rates);
+
+static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
+{
+	struct tegra_emc *emc = data;
+
+	*rate = emc->debugfs.min_rate;
+
+	return 0;
+}
+
+static int tegra_emc_debug_min_rate_set(void *data, u64 rate)
+{
+	struct tegra_emc *emc = data;
+	int err;
+
+	if (!tegra_emc_validate_rate(emc, rate))
+		return -EINVAL;
+
+	err = emc_set_min_rate(emc, rate, EMC_RATE_DEBUG);
+	if (err < 0)
+		return err;
+
+	emc->debugfs.min_rate = rate;
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(tegra_emc_debug_min_rate_fops,
+			tegra_emc_debug_min_rate_get,
+			tegra_emc_debug_min_rate_set, "%llu\n");
+
+static int tegra_emc_debug_max_rate_get(void *data, u64 *rate)
+{
+	struct tegra_emc *emc = data;
+
+	*rate = emc->debugfs.max_rate;
+
+	return 0;
+}
+
+static int tegra_emc_debug_max_rate_set(void *data, u64 rate)
+{
+	struct tegra_emc *emc = data;
+	int err;
+
+	if (!tegra_emc_validate_rate(emc, rate))
+		return -EINVAL;
+
+	err = emc_set_max_rate(emc, rate, EMC_RATE_DEBUG);
+	if (err < 0)
+		return err;
+
+	emc->debugfs.max_rate = rate;
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(tegra_emc_debug_max_rate_fops,
+			tegra_emc_debug_max_rate_get,
+			tegra_emc_debug_max_rate_set, "%llu\n");
+
+static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc)
+{
+	unsigned int i;
+	int err;
+
+	emc->debugfs.min_rate = ULONG_MAX;
+	emc->debugfs.max_rate = 0;
+
+	for (i = 0; i < emc->num_timings; i++) {
+		if (emc->timings[i].rate < emc->debugfs.min_rate)
+			emc->debugfs.min_rate = emc->timings[i].rate;
+
+		if (emc->timings[i].rate > emc->debugfs.max_rate)
+			emc->debugfs.max_rate = emc->timings[i].rate;
+	}
+
+	if (!emc->num_timings) {
+		emc->debugfs.min_rate = clk_get_rate(emc->clk);
+		emc->debugfs.max_rate = emc->debugfs.min_rate;
+	}
+
+	err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
+				 emc->debugfs.max_rate);
+	if (err < 0) {
+		dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
+			emc->debugfs.min_rate, emc->debugfs.max_rate,
+			emc->clk);
+		return;
+	}
+
+	emc->debugfs.root = debugfs_create_dir("emc", NULL);
+
+	debugfs_create_file("available_rates", 0444, emc->debugfs.root, emc,
+			    &tegra_emc_debug_available_rates_fops);
+	debugfs_create_file("min_rate", 0644, emc->debugfs.root,
+			    emc, &tegra_emc_debug_min_rate_fops);
+	debugfs_create_file("max_rate", 0644, emc->debugfs.root,
+			    emc, &tegra_emc_debug_max_rate_fops);
+}
+
+static inline struct tegra_emc *
+to_tegra_emc_provider(struct icc_provider *provider)
+{
+	return container_of(provider, struct tegra_emc, provider);
+}
+
+static struct icc_node_data *
+emc_of_icc_xlate_extended(struct of_phandle_args *spec, void *data)
+{
+	struct icc_provider *provider = data;
+	struct icc_node_data *ndata;
+	struct icc_node *node;
+
+	/* External Memory is the only possible ICC route */
+	list_for_each_entry(node, &provider->nodes, node_list) {
+		if (node->id != TEGRA_ICC_EMEM)
+			continue;
+
+		ndata = kzalloc(sizeof(*ndata), GFP_KERNEL);
+		if (!ndata)
+			return ERR_PTR(-ENOMEM);
+
+		/*
+		 * SRC and DST nodes should have matching TAG in order to have
+		 * it set by default for a requested path.
+		 */
+		ndata->tag = TEGRA_MC_ICC_TAG_ISO;
+		ndata->node = node;
+
+		return ndata;
+	}
+
+	return ERR_PTR(-EPROBE_DEFER);
+}
+
+static int emc_icc_set(struct icc_node *src, struct icc_node *dst)
+{
+	struct tegra_emc *emc = to_tegra_emc_provider(dst->provider);
+	unsigned long long peak_bw = icc_units_to_bps(dst->peak_bw);
+	unsigned long long avg_bw = icc_units_to_bps(dst->avg_bw);
+	unsigned long long rate = max(avg_bw, peak_bw);
+	unsigned int dram_data_bus_width_bytes;
+	const unsigned int ddr = 2;
+	int err;
+
+	/*
+	 * Tegra124 EMC runs on a clock rate of SDRAM bus. This means that
+	 * EMC clock rate is twice smaller than the peak data rate because
+	 * data is sampled on both EMC clock edges.
+	 */
+	dram_data_bus_width_bytes = emc->dram_bus_width / 8;
+	do_div(rate, ddr * dram_data_bus_width_bytes);
+	rate = min_t(u64, rate, U32_MAX);
+
+	err = emc_set_min_rate(emc, rate, EMC_RATE_ICC);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int tegra_emc_interconnect_init(struct tegra_emc *emc)
+{
+	const struct tegra_mc_soc *soc = emc->mc->soc;
+	struct icc_node *node;
+	int err;
+
+	emc->provider.dev = emc->dev;
+	emc->provider.set = emc_icc_set;
+	emc->provider.data = &emc->provider;
+	emc->provider.aggregate = soc->icc_ops->aggregate;
+	emc->provider.xlate_extended = emc_of_icc_xlate_extended;
+
+	icc_provider_init(&emc->provider);
+
+	/* create External Memory Controller node */
+	node = icc_node_create(TEGRA_ICC_EMC);
+	if (IS_ERR(node)) {
+		err = PTR_ERR(node);
+		goto err_msg;
+	}
+
+	node->name = "External Memory Controller";
+	icc_node_add(node, &emc->provider);
+
+	/* link External Memory Controller to External Memory (DRAM) */
+	err = icc_link_create(node, TEGRA_ICC_EMEM);
+	if (err)
+		goto remove_nodes;
+
+	/* create External Memory node */
+	node = icc_node_create(TEGRA_ICC_EMEM);
+	if (IS_ERR(node)) {
+		err = PTR_ERR(node);
+		goto remove_nodes;
+	}
+
+	node->name = "External Memory (DRAM)";
+	icc_node_add(node, &emc->provider);
+
+	err = icc_provider_register(&emc->provider);
+	if (err)
+		goto remove_nodes;
+
+	return 0;
+
+remove_nodes:
+	icc_nodes_remove(&emc->provider);
+err_msg:
+	dev_err(emc->dev, "failed to initialize ICC: %d\n", err);
+
+	return err;
+}
+
+static int tegra_emc_opp_table_init(struct tegra_emc *emc)
+{
+	u32 hw_version = BIT(tegra_sku_info.soc_speedo_id);
+	int opp_token, err;
+
+	err = dev_pm_opp_set_supported_hw(emc->dev, &hw_version, 1);
+	if (err < 0) {
+		dev_err(emc->dev, "failed to set OPP supported HW: %d\n", err);
+		return err;
+	}
+	opp_token = err;
+
+	err = dev_pm_opp_of_add_table(emc->dev);
+	if (err) {
+		if (err == -ENODEV)
+			dev_err(emc->dev, "OPP table not found, please update your device tree\n");
+		else
+			dev_err(emc->dev, "failed to add OPP table: %d\n", err);
+
+		goto put_hw_table;
+	}
+
+	dev_info_once(emc->dev, "OPP HW ver. 0x%x, current clock rate %lu MHz\n",
+		      hw_version, clk_get_rate(emc->clk) / 1000000);
+
+	/* first dummy rate-set initializes voltage state */
+	err = dev_pm_opp_set_rate(emc->dev, clk_get_rate(emc->clk));
+	if (err) {
+		dev_err(emc->dev, "failed to initialize OPP clock: %d\n", err);
+		goto remove_table;
+	}
+
+	return 0;
+
+remove_table:
+	dev_pm_opp_of_remove_table(emc->dev);
+put_hw_table:
+	dev_pm_opp_put_supported_hw(opp_token);
+
+	return err;
+}
+
+static void devm_tegra_emc_unset_callback(void *data)
+{
+	tegra124_clk_set_emc_callbacks(NULL, NULL);
+}
+
+static int tegra_emc_probe(struct platform_device *pdev)
+{
+	struct device_node *np;
+	struct tegra_emc *emc;
+	u32 ram_code;
+	int err;
+
+	emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL);
+	if (!emc)
+		return -ENOMEM;
+
+	mutex_init(&emc->rate_lock);
+	emc->dev = &pdev->dev;
+
+	emc->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(emc->regs))
+		return PTR_ERR(emc->regs);
+
+	emc->mc = devm_tegra_memory_controller_get(&pdev->dev);
+	if (IS_ERR(emc->mc))
+		return PTR_ERR(emc->mc);
+
+	ram_code = tegra_read_ram_code();
+
+	np = tegra_emc_find_node_by_ram_code(pdev->dev.of_node, ram_code);
+	if (np) {
+		err = tegra_emc_load_timings_from_dt(emc, np);
+		of_node_put(np);
+		if (err)
+			return err;
+	} else {
+		dev_info_once(&pdev->dev,
+			      "no memory timings for RAM code %u found in DT\n",
+			      ram_code);
+	}
+
+	err = emc_init(emc);
+	if (err) {
+		dev_err(&pdev->dev, "EMC initialization failed: %d\n", err);
+		return err;
+	}
+
+	platform_set_drvdata(pdev, emc);
+
+	tegra124_clk_set_emc_callbacks(tegra_emc_prepare_timing_change,
+				       tegra_emc_complete_timing_change);
+
+	err = devm_add_action_or_reset(&pdev->dev, devm_tegra_emc_unset_callback,
+				       NULL);
+	if (err)
+		return err;
+
+	emc->clk = devm_clk_get(&pdev->dev, "emc");
+	if (IS_ERR(emc->clk)) {
+		err = PTR_ERR(emc->clk);
+		dev_err(&pdev->dev, "failed to get EMC clock: %d\n", err);
+		return err;
+	}
+
+	err = tegra_emc_opp_table_init(emc);
+	if (err)
+		return err;
+
+	tegra_emc_rate_requests_init(emc);
+
+	if (IS_ENABLED(CONFIG_DEBUG_FS))
+		emc_debugfs_init(&pdev->dev, emc);
+
+	tegra_emc_interconnect_init(emc);
+
+	/*
+	 * Don't allow the kernel module to be unloaded. Unloading adds some
+	 * extra complexity which doesn't really worth the effort in a case of
+	 * this driver.
+	 */
+	try_module_get(THIS_MODULE);
+
+	return 0;
+};
+
+static struct platform_driver tegra_emc_driver = {
+	.probe = tegra_emc_probe,
+	.driver = {
+		.name = "tegra-emc",
+		.of_match_table = tegra_emc_of_match,
+		.suppress_bind_attrs = true,
+		.sync_state = icc_sync_state,
+	},
+};
+module_platform_driver(tegra_emc_driver);
+
+MODULE_AUTHOR("Mikko Perttunen <mperttunen@nvidia.com>");
+MODULE_DESCRIPTION("NVIDIA Tegra124 EMC driver");
+MODULE_LICENSE("GPL v2");