[U-Boot] [PATCH 06/14] tegra: Add EMC support for optimal memory timings

Simon Glass sjg at chromium.org
Mon Dec 26 20:32:59 CET 2011


From: Jimmy Zhang <jimmzhang at nvidia.com>

Add support for setting up the memory controller parameters. Boards
can call tegra_set_emc() with a table containing the required
parameters.

Signed-off-by: Simon Glass <sjg at chromium.org>
---
 arch/arm/cpu/armv7/tegra2/Makefile        |    1 +
 arch/arm/cpu/armv7/tegra2/emc.c           |  165 +++++++++++++++++++++++++++++
 arch/arm/include/asm/arch-tegra2/emc.h    |  107 +++++++++++++++++++
 arch/arm/include/asm/arch-tegra2/tegra2.h |    1 +
 4 files changed, 274 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/cpu/armv7/tegra2/emc.c
 create mode 100644 arch/arm/include/asm/arch-tegra2/emc.h

diff --git a/arch/arm/cpu/armv7/tegra2/Makefile b/arch/arm/cpu/armv7/tegra2/Makefile
index e9ac6c9..dcd6329 100644
--- a/arch/arm/cpu/armv7/tegra2/Makefile
+++ b/arch/arm/cpu/armv7/tegra2/Makefile
@@ -34,6 +34,7 @@ LIB	=  $(obj)lib$(SOC).o
 
 SOBJS	:= lowlevel_init.o
 COBJS-y	:= ap20.o board.o clock.o funcmux.o pinmux.o sys_info.o timer.o
+COBJS-$(CONFIG_TEGRA_CLOCK_SCALING) += emc.o
 COBJS-$(CONFIG_USB_EHCI_TEGRA) += usb.o
 
 COBJS	:= $(COBJS-y)
diff --git a/arch/arm/cpu/armv7/tegra2/emc.c b/arch/arm/cpu/armv7/tegra2/emc.c
new file mode 100644
index 0000000..563fe89
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra2/emc.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/ap20.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/emc.h>
+#include <asm/arch/tegra2.h>
+
+static const struct tegra_emc_table *tegra_emc_table;
+static int tegra_emc_table_size;
+
+static inline void emc_writel(u32 val, unsigned long addr)
+{
+	writel(val, TEGRA2_EMC_BASE + addr);
+}
+
+static inline u32 emc_readl(unsigned long addr)
+{
+	return readl(TEGRA2_EMC_BASE + addr);
+}
+
+/*
+ * This table defines the ordering of the registers provided to
+ * tegra_set_mmc()
+ * TODO: Convert to fdt version once available
+ */
+static const unsigned long emc_reg_addr[TEGRA_EMC_NUM_REGS] = {
+	0x2c,	/* RC */
+	0x30,	/* RFC */
+	0x34,	/* RAS */
+	0x38,	/* RP */
+	0x3c,	/* R2W */
+	0x40,	/* W2R */
+	0x44,	/* R2P */
+	0x48,	/* W2P */
+	0x4c,	/* RD_RCD */
+	0x50,	/* WR_RCD */
+	0x54,	/* RRD */
+	0x58,	/* REXT */
+	0x5c,	/* WDV */
+	0x60,	/* QUSE */
+	0x64,	/* QRST */
+	0x68,	/* QSAFE */
+	0x6c,	/* RDV */
+	0x70,	/* REFRESH */
+	0x74,	/* BURST_REFRESH_NUM */
+	0x78,	/* PDEX2WR */
+	0x7c,	/* PDEX2RD */
+	0x80,	/* PCHG2PDEN */
+	0x84,	/* ACT2PDEN */
+	0x88,	/* AR2PDEN */
+	0x8c,	/* RW2PDEN */
+	0x90,	/* TXSR */
+	0x94,	/* TCKE */
+	0x98,	/* TFAW */
+	0x9c,	/* TRPAB */
+	0xa0,	/* TCLKSTABLE */
+	0xa4,	/* TCLKSTOP */
+	0xa8,	/* TREFBW */
+	0xac,	/* QUSE_EXTRA */
+	0x114,	/* FBIO_CFG6 */
+	0xb0,	/* ODT_WRITE */
+	0xb4,	/* ODT_READ */
+	0x104,	/* FBIO_CFG5 */
+	0x2bc,	/* CFG_DIG_DLL */
+	0x2c0,	/* DLL_XFORM_DQS */
+	0x2c4,	/* DLL_XFORM_QUSE */
+	0x2e0,	/* ZCAL_REF_CNT */
+	0x2e4,	/* ZCAL_WAIT_CNT */
+	0x2a8,	/* AUTO_CAL_INTERVAL */
+	0x2d0,	/* CFG_CLKTRIM_0 */
+	0x2d4,	/* CFG_CLKTRIM_1 */
+	0x2d8,	/* CFG_CLKTRIM_2 */
+};
+
+/* The EMC registers have shadow registers.  When the EMC clock is updated
+ * in the clock controller, the shadow registers are copied to the active
+ * registers, allowing glitchless memory bus frequency changes.
+ * This function updates the shadow registers for a new clock frequency,
+ * and relies on the clock lock on the emc clock to avoid races between
+ * multiple frequency changes */
+#define EMC_SDRAM_RATE_T20	(333000 * 2 * 1000)
+#define EMC_SDRAM_RATE_T25	(380000 * 2 * 1000)
+
+static int tegra_emc_set_rate(unsigned long rate)
+{
+	int i;
+	int j;
+
+	if (!tegra_emc_table)
+		return -1;
+
+	/* The EMC clock rate is twice the bus rate, and the bus rate is
+	 * measured in kHz */
+	rate = rate / 2 / 1000;
+
+	for (i = 0; i < tegra_emc_table_size; i++)
+		if (tegra_emc_table[i].rate == rate)
+			break;
+
+	if (i >= tegra_emc_table_size)
+		return -1;
+
+	for (j = 0; j < TEGRA_EMC_NUM_REGS; j++)
+		emc_writel(tegra_emc_table[i].regs[j], emc_reg_addr[j]);
+
+	/*
+	 * trigger emc with new settings by updating clk_rst's source EMC
+	 * Set PLLM_OUT0 (bits: 31:30= 0) and divisor bits 7:0 = 0 (ie 1)
+	 */
+	clock_ll_set_source_divisor(PERIPH_ID_EMC, 0, 0);
+	udelay(1);
+	return 0;
+}
+
+int tegra_set_emc(const struct tegra_emc_table *table, int table_size)
+{
+	unsigned long rate;
+
+	if (!table) {
+		tegra_emc_table = NULL;
+		tegra_emc_table_size = 0;
+		return -1;
+	}
+
+	tegra_emc_table = table;
+	tegra_emc_table_size = table_size;
+
+	switch (tegra_get_chip_type()) {
+	case TEGRA_SOC_T20:
+		rate  = EMC_SDRAM_RATE_T20;
+		break;
+	case TEGRA_SOC_T25:
+		rate  = EMC_SDRAM_RATE_T25;
+		break;
+	default:
+		/* unknown chip type, no clk change*/
+		return -1;
+	}
+
+	tegra_emc_set_rate(rate);
+
+	return 0;
+}
diff --git a/arch/arm/include/asm/arch-tegra2/emc.h b/arch/arm/include/asm/arch-tegra2/emc.h
new file mode 100644
index 0000000..a1d1e9d
--- /dev/null
+++ b/arch/arm/include/asm/arch-tegra2/emc.h
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * (C) Copyright 2010,2011 NVIDIA Corporation <www.nvidia.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _ARCH_EMC_H_
+#define _ARCH_EMC_H_
+
+#include <asm/types.h>
+
+#define TEGRA_EMC_NUM_REGS	46
+
+struct tegra_emc_table {
+	unsigned long rate;
+	u32 regs[TEGRA_EMC_NUM_REGS];
+};
+
+/* EMC Registers */
+struct emc_ctlr {
+	u32 cfg;		/* 0x00: EMC_CFG */
+	u32 reserved0[3];	/* 0x04 ~ 0x0C */
+	u32 adr_cfg;		/* 0x10: EMC_ADR_CFG */
+	u32 adr_cfg1;		/* 0x14: EMC_ADR_CFG_1 */
+	u32 reserved1[2];	/* 0x18 ~ 0x18 */
+	u32 refresh_ctrl;	/* 0x20: EMC_REFCTRL */
+	u32 pin;		/* 0x24: EMC_PIN */
+	u32 timing_ctrl;	/* 0x28: EMC_TIMING_CONTROL */
+	u32 rc;			/* 0x2C: EMC_RC */
+	u32 rfc;		/* 0x30: EMC_RFC */
+	u32 ras;		/* 0x34: EMC_RAS */
+	u32 rp;			/* 0x38: EMC_RP */
+	u32 r2w;		/* 0x3C: EMC_R2W */
+	u32 w2r;		/* 0x40: EMC_W2R */
+	u32 r2p;		/* 0x44: EMC_R2P */
+	u32 w2p;		/* 0x48: EMC_W2P */
+	u32 rd_rcd;		/* 0x4C: EMC_RD_RCD */
+	u32 wd_rcd;		/* 0x50: EMC_WD_RCD */
+	u32 rrd;		/* 0x54: EMC_RRD */
+	u32 rext;		/* 0x58: EMC_REXT */
+	u32 wdv;		/* 0x5C: EMC_WDV */
+	u32 quse;		/* 0x60: EMC_QUSE */
+	u32 qrst;		/* 0x64: EMC_QRST */
+	u32 qsafe;		/* 0x68: EMC_QSAFE */
+	u32 rdv;		/* 0x6C: EMC_RDV */
+	u32 refresh;		/* 0x70: EMC_REFRESH */
+	u32 burst_refresh_num;	/* 0x74: EMC_BURST_REFRESH_NUM */
+	u32 pdex2wr;		/* 0x78: EMC_PDEX2WR */
+	u32 pdex2rd;		/* 0x7c: EMC_PDEX2RD */
+	u32 pchg2pden;		/* 0x80: EMC_PCHG2PDEN */
+	u32 act2pden;		/* 0x84: EMC_ACT2PDEN */
+	u32 ar2pden;		/* 0x88: EMC_AR2PDEN */
+	u32 rw2pden;		/* 0x8C: EMC_RW2PDEN */
+	u32 txsr;		/* 0x90: EMC_TXSR */
+	u32 tcke;		/* 0x94: EMC_TCKE */
+	u32 tfaw;		/* 0x98: EMC_TFAW */
+	u32 trpab;		/* 0x9C: EMC_TRPAB */
+	u32 tclkstable;		/* 0xA0: EMC_TCLKSTABLE */
+	u32 tclkstop;		/* 0xA4: EMC_TCLKSTOP */
+	u32 trefbw;		/* 0xA8: EMC_TREFBW */
+	u32 quse_extra;		/* 0xAC: EMC_QUSE_EXTRA */
+	u32 odt_write;		/* 0xB0: EMC_ODT_WRITE */
+	u32 odt_read;		/* 0xB4: EMC_ODT_READ */
+	u32 reserved2[5];	/* 0xB8 ~ 0xC8 */
+	u32 mrs;		/* 0xCC: EMC_MRS */
+	u32 emrs;		/* 0xD0: EMC_EMRS */
+	u32 ref;		/* 0xD4: EMC_REF */
+	u32 pre;		/* 0xD8: EMC_PRE */
+	u32 nop;		/* 0xDC: EMC_NOP */
+	u32 self_ref;		/* 0xE0: EMC_SELF_REF */
+	u32 dpd;		/* 0xE4: EMC_DPD */
+	u32 mrw;		/* 0xE8: EMC_MRW */
+	u32 mrr;		/* 0xEC: EMC_MRR */
+	u32 reserved3;		/* 0xF0: */
+	u32 fbio_cfg1;		/* 0xF4: EMC_FBIO_CFG1 */
+	u32 fbio_dqsib_dly;	/* 0xF8: EMC_FBIO_DQSIB_DLY */
+	u32 fbio_dqsib_dly_msb;	/* 0xFC: EMC_FBIO_DQSIB_DLY_MSG */
+	u32 fbio_spare;		/* 0x100: SBIO_SPARE */
+				/* There are more registers ... */
+};
+
+/**
+ * Set up the memory timings according to a provided table
+ *
+ * @param table		Memory timing table
+ * @param table_size	Number of entries in table
+ */
+int tegra_set_emc(const struct tegra_emc_table *table, int table_size);
+
+#endif
diff --git a/arch/arm/include/asm/arch-tegra2/tegra2.h b/arch/arm/include/asm/arch-tegra2/tegra2.h
index f33726d..480ec0c 100644
--- a/arch/arm/include/asm/arch-tegra2/tegra2.h
+++ b/arch/arm/include/asm/arch-tegra2/tegra2.h
@@ -44,6 +44,7 @@
 #define TEGRA2_I2C2_BASE	(NV_PA_APB_MISC_BASE + 0xC400)
 #define TEGRA2_I2C3_BASE	(NV_PA_APB_MISC_BASE + 0xC500)
 #define TEGRA2_DVC_BASE		(NV_PA_APB_MISC_BASE + 0xD000)
+#define TEGRA2_EMC_BASE		(NV_PA_APB_MISC_BASE + 0xF400)
 #define TEGRA2_FUSE_BASE	(NV_PA_APB_MISC_BASE + 0xF800)
 #define NV_PA_CSITE_BASE	0x70040000
 #define TEGRA_USB1_BASE		0xC5000000
-- 
1.7.3.1



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