[U-Boot] [PATCH 8/9] imx: mx6: ddr: add LPDDR2 support
Peng Fan
Peng.Fan at freescale.com
Mon Aug 17 05:29:25 CEST 2015
Add LPDDR2 support:
1. Implement a function mx6_lpddr2_cfg to initialize MMDC for LPDDR2.
2. Introduce a structure mx6_lpddr2_cfg, most entrys are same to
mx6_ddr3_cfg, but still keep it a single one for easy to choose
parameters for LPDDR2.
3. If ddr_type is LPDDR2, use mx6_lpddr2_cfg to init MMDC.
4. Update comments.
Signed-off-by: Peng Fan <Peng.Fan at freescale.com>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Tim Harvey <tharvey at gateworks.com>
---
arch/arm/cpu/armv7/mx6/ddr.c | 300 +++++++++++++++++++++++++++++++-
arch/arm/include/asm/arch-mx6/mx6-ddr.h | 15 ++
2 files changed, 311 insertions(+), 4 deletions(-)
diff --git a/arch/arm/cpu/armv7/mx6/ddr.c b/arch/arm/cpu/armv7/mx6/ddr.c
index a6bef60..1e78b9c 100644
--- a/arch/arm/cpu/armv7/mx6/ddr.c
+++ b/arch/arm/cpu/armv7/mx6/ddr.c
@@ -7,6 +7,7 @@
#include <common.h>
#include <linux/types.h>
+#include <asm/arch/clock.h>
#include <asm/arch/mx6-ddr.h>
#include <asm/arch/sys_proto.h>
#include <asm/io.h>
@@ -330,15 +331,20 @@ void mx6sdl_dram_iocfg(unsigned width,
* Configure mx6 mmdc registers based on:
* - board-specific memory configuration
* - board-specific calibration data
- * - ddr3 chip details
+ * - ddr3/lpddr2 chip details
*
* The various calculations here are derived from the Freescale
- * i.Mx6DQSDL DDR3 Script Aid spreadsheet (DOC-94917) designed to generate MMDC
- * configuration registers based on memory system and memory chip parameters.
+ * 1. i.Mx6DQSDL DDR3 Script Aid spreadsheet (DOC-94917) designed to generate
+ * MMDC configuration registers based on memory system and memory chip
+ * parameters.
+ *
+ * 2. i.Mx6SL LPDDR2 Script Aid spreadsheet V0.04 designed to generate MMDC
+ * configuration registers based on memory system and memory chip
+ * parameters.
*
* The defaults here are those which were specified in the spreadsheet.
* For details on each register, refer to the IMX6DQRM and/or IMX6SDLRM
- * section titled MMDC initialization
+ * and/or IMX6SLRM section titled MMDC initialization.
*/
#define MR(val, ba, cmd, cs1) \
((val << 16) | (1 << 15) | (cmd << 4) | (cs1 << 3) | ba)
@@ -348,6 +354,290 @@ void mx6sdl_dram_iocfg(unsigned width,
mmdc1->entry = value; \
} while (0)
+/*
+ * According JESD209-2B-LPDDR2: Table 103
+ * WL: write latency
+ */
+static int lpddr2_wl(uint32_t mem_speed)
+{
+ switch (mem_speed) {
+ case 1066:
+ case 933:
+ return 4;
+ case 800:
+ return 3;
+ case 677:
+ case 533:
+ return 2;
+ case 400:
+ case 333:
+ return 1;
+ default:
+ puts("invalid memory speed\n");
+ hang();
+ }
+
+ return 0;
+}
+
+/*
+ * According JESD209-2B-LPDDR2: Table 103
+ * RL: read latency
+ */
+static int lpddr2_rl(uint32_t mem_speed)
+{
+ switch (mem_speed) {
+ case 1066:
+ return 8;
+ case 933:
+ return 7;
+ case 800:
+ return 6;
+ case 677:
+ return 5;
+ case 533:
+ return 4;
+ case 400:
+ case 333:
+ return 3;
+ default:
+ puts("invalid memory speed\n");
+ hang();
+ }
+
+ return 0;
+}
+
+void mx6_lpddr2_cfg(const struct mx6_ddr_sysinfo *sysinfo,
+ const struct mx6_mmdc_calibration *calib,
+ const struct mx6_lpddr2_cfg *lpddr2_cfg)
+{
+ volatile struct mmdc_p_regs *mmdc0;
+ u32 val;
+ u8 tcke, tcksrx, tcksre, trrd;
+ u8 twl, txp, tfaw, tcl;
+ u16 tras, twr, tmrd, trtp, twtr, trfc, txsr;
+ u16 trcd_lp, trppb_lp, trpab_lp, trc_lp;
+ u16 cs0_end;
+ u8 coladdr;
+ int clkper; /* clock period in picoseconds */
+ int clock; /* clock freq in mHz */
+ int cs;
+
+ /* only support 16/32 bits */
+ if (sysinfo->dsize > 1)
+ hang();
+
+ mmdc0 = (struct mmdc_p_regs *)MMDC_P0_BASE_ADDR;
+
+ clock = mxc_get_clock(MXC_DDR_CLK) / 1000000U;
+ clkper = (1000 * 1000) / clock; /* pico seconds */
+
+ twl = lpddr2_wl(lpddr2_cfg->mem_speed) - 1;
+
+ /* LPDDR2-S2 and LPDDR2-S4 have the same tRFC value. */
+ switch (lpddr2_cfg->density) {
+ case 1:
+ case 2:
+ case 4:
+ trfc = DIV_ROUND_UP(130000, clkper) - 1;
+ txsr = DIV_ROUND_UP(140000, clkper) - 1;
+ break;
+ case 8:
+ trfc = DIV_ROUND_UP(210000, clkper) - 1;
+ txsr = DIV_ROUND_UP(220000, clkper) - 1;
+ break;
+ default:
+ /*
+ * 64Mb, 128Mb, 256Mb, 512Mb are not supported currently.
+ */
+ hang();
+ break;
+ }
+ /*
+ * txpdll, txpr, taonpd and taofpd are not relevant in LPDDR2 mode,
+ * set them to 0. */
+ txp = DIV_ROUND_UP(7500, clkper) - 1;
+ tcke = 3;
+ if (lpddr2_cfg->mem_speed == 333)
+ tfaw = DIV_ROUND_UP(60000, clkper) - 1;
+ else
+ tfaw = DIV_ROUND_UP(50000, clkper) - 1;
+ trrd = DIV_ROUND_UP(10000, clkper) - 1;
+
+ /* tckesr for LPDDR2 */
+ tcksre = DIV_ROUND_UP(15000, clkper);
+ tcksrx = tcksre;
+ twr = DIV_ROUND_UP(15000, clkper) - 1;
+ /*
+ * tMRR: 2, tMRW: 5
+ * tMRD should be set to max(tMRR, tMRW)
+ */
+ tmrd = 5;
+ tras = DIV_ROUND_UP(lpddr2_cfg->trasmin, clkper / 10) - 1;
+ /* LPDDR2 mode use tRCD_LP filed in MDCFG3. */
+ trcd_lp = DIV_ROUND_UP(lpddr2_cfg->trcd_lp, clkper / 10) - 1;
+ trc_lp = DIV_ROUND_UP(lpddr2_cfg->trasmin + lpddr2_cfg->trppb_lp,
+ clkper / 10) - 1;
+ trppb_lp = DIV_ROUND_UP(lpddr2_cfg->trppb_lp, clkper / 10) - 1;
+ trpab_lp = DIV_ROUND_UP(lpddr2_cfg->trpab_lp, clkper / 10) - 1;
+ /* To LPDDR2, CL in MDCFG0 refers to RL */
+ tcl = lpddr2_rl(lpddr2_cfg->mem_speed) - 3;
+ twtr = DIV_ROUND_UP(7500, clkper) - 1;
+ trtp = DIV_ROUND_UP(7500, clkper) - 1;
+
+ cs0_end = 4 * sysinfo->cs_density - 1;
+
+ debug("density:%d Gb (%d Gb per chip)\n",
+ sysinfo->cs_density, lpddr2_cfg->density);
+ debug("clock: %dMHz (%d ps)\n", clock, clkper);
+ debug("memspd:%d\n", lpddr2_cfg->mem_speed);
+ debug("trcd_lp=%d\n", trcd_lp);
+ debug("trppb_lp=%d\n", trppb_lp);
+ debug("trpab_lp=%d\n", trpab_lp);
+ debug("trc_lp=%d\n", trc_lp);
+ debug("tcke=%d\n", tcke);
+ debug("tcksrx=%d\n", tcksrx);
+ debug("tcksre=%d\n", tcksre);
+ debug("trfc=%d\n", trfc);
+ debug("txsr=%d\n", txsr);
+ debug("txp=%d\n", txp);
+ debug("tfaw=%d\n", tfaw);
+ debug("tcl=%d\n", tcl);
+ debug("tras=%d\n", tras);
+ debug("twr=%d\n", twr);
+ debug("tmrd=%d\n", tmrd);
+ debug("twl=%d\n", twl);
+ debug("trtp=%d\n", trtp);
+ debug("twtr=%d\n", twtr);
+ debug("trrd=%d\n", trrd);
+ debug("cs0_end=%d\n", cs0_end);
+ debug("ncs=%d\n", sysinfo->ncs);
+
+ /*
+ * board-specific configuration:
+ * These values are determined empirically and vary per board layout
+ */
+ mmdc0->mpwldectrl0 = calib->p0_mpwldectrl0;
+ mmdc0->mpwldectrl1 = calib->p0_mpwldectrl1;
+ mmdc0->mpdgctrl0 = calib->p0_mpdgctrl0;
+ mmdc0->mpdgctrl1 = calib->p0_mpdgctrl1;
+ mmdc0->mprddlctl = calib->p0_mprddlctl;
+ mmdc0->mpwrdlctl = calib->p0_mpwrdlctl;
+ mmdc0->mpzqlp2ctl = calib->mpzqlp2ctl;
+
+ /* Read data DQ Byte0-3 delay */
+ mmdc0->mprddqby0dl = 0x33333333;
+ mmdc0->mprddqby1dl = 0x33333333;
+ if (sysinfo->dsize > 0) {
+ mmdc0->mprddqby2dl = 0x33333333;
+ mmdc0->mprddqby3dl = 0x33333333;
+ }
+
+ /* Write data DQ Byte0-3 delay */
+ mmdc0->mpwrdqby0dl = 0xf3333333;
+ mmdc0->mpwrdqby1dl = 0xf3333333;
+ if (sysinfo->dsize > 0) {
+ mmdc0->mpwrdqby2dl = 0xf3333333;
+ mmdc0->mpwrdqby3dl = 0xf3333333;
+ }
+
+ /*
+ * In LPDDR2 mode this register should be cleared,
+ * so no termination will be activated.
+ */
+ mmdc0->mpodtctrl = 0;
+
+ /* complete calibration */
+ val = (1 << 11); /* Force measurement on delay-lines */
+ mmdc0->mpmur0 = val;
+
+ /* Step 1: configuration request */
+ mmdc0->mdscr = (u32)(1 << 15); /* config request */
+
+ /* Step 2: Timing configuration */
+ mmdc0->mdcfg0 = (trfc << 24) | (txsr << 16) | (txp << 13) |
+ (tfaw << 4) | tcl;
+ mmdc0->mdcfg1 = (tras << 16) | (twr << 9) | (tmrd << 5) | twl;
+ mmdc0->mdcfg2 = (trtp << 6) | (twtr << 3) | trrd;
+ mmdc0->mdcfg3lp = (trc_lp << 16) | (trcd_lp << 8) |
+ (trppb_lp << 4) | trpab_lp;
+ mmdc0->mdotc = 0;
+
+ mmdc0->mdasp = cs0_end; /* CS addressing */
+
+ /* Step 3: Configure DDR type */
+ mmdc0->mdmisc = (sysinfo->cs1_mirror << 19) | (sysinfo->walat << 16) |
+ (sysinfo->bi_on << 12) | (sysinfo->mif3_mode << 9) |
+ (sysinfo->ralat << 6) | (1 << 3);
+
+ /* Step 4: Configure delay while leaving reset */
+ mmdc0->mdor = (sysinfo->sde_to_rst << 8) |
+ (sysinfo->rst_to_cke << 0);
+
+ /* Step 5: Configure DDR physical parameters (density and burst len) */
+ coladdr = lpddr2_cfg->coladdr;
+ if (lpddr2_cfg->coladdr == 8) /* 8-bit COL is 0x3 */
+ coladdr += 4;
+ else if (lpddr2_cfg->coladdr == 12) /* 12-bit COL is 0x4 */
+ coladdr += 1;
+ mmdc0->mdctl = (lpddr2_cfg->rowaddr - 11) << 24 | /* ROW */
+ (coladdr - 9) << 20 | /* COL */
+ (0 << 19) | /* Burst Length = 4 for LPDDR2 */
+ (sysinfo->dsize << 16); /* DDR data bus size */
+
+ /* Step 6: Perform ZQ calibration */
+ val = 0xa1390003; /* one-time HW ZQ calib */
+ mmdc0->mpzqhwctrl = val;
+
+ /* Step 7: Enable MMDC with desired chip select */
+ mmdc0->mdctl |= (1 << 31) | /* SDE_0 for CS0 */
+ ((sysinfo->ncs == 2) ? 1 : 0) << 30; /* SDE_1 for CS1 */
+
+ /* Step 8: Write Mode Registers to Init LPDDR2 devices */
+ for (cs = 0; cs < sysinfo->ncs; cs++) {
+ /* MR63: reset */
+ mmdc0->mdscr = MR(63, 0, 3, cs);
+ /* MR10: calibration,
+ * 0xff is calibration command after intilization.
+ */
+ val = 0xA | (0xff << 8);
+ mmdc0->mdscr = MR(val, 0, 3, cs);
+ /* MR1 */
+ val = 0x1 | (0x82 << 8);
+ mmdc0->mdscr = MR(val, 0, 3, cs);
+ /* MR2 */
+ val = 0x2 | (0x04 << 8);
+ mmdc0->mdscr = MR(val, 0, 3, cs);
+ /* MR3 */
+ val = 0x3 | (0x02 << 8);
+ mmdc0->mdscr = MR(val, 0, 3, cs);
+ }
+
+ /* Step 10: Power down control and self-refresh */
+ mmdc0->mdpdc = (tcke & 0x7) << 16 |
+ 5 << 12 | /* PWDT_1: 256 cycles */
+ 5 << 8 | /* PWDT_0: 256 cycles */
+ 1 << 6 | /* BOTH_CS_PD */
+ (tcksrx & 0x7) << 3 |
+ (tcksre & 0x7);
+ mmdc0->mapsr = 0x00001006; /* ADOPT power down enabled */
+
+ /* Step 11: Configure ZQ calibration: one-time and periodic 1ms */
+ val = 0xa1310003;
+ mmdc0->mpzqhwctrl = val;
+
+ /* Step 12: Configure and activate periodic refresh */
+ mmdc0->mdref = (0 << 14) | /* REF_SEL: Periodic refresh cycle: 64kHz */
+ (3 << 11); /* REFR: Refresh Rate - 4 refreshes */
+
+ /* Step 13: Deassert config request - init complete */
+ mmdc0->mdscr = 0x00000000;
+
+ /* wait for auto-ZQ calibration to complete */
+ mdelay(1);
+}
+
void mx6_ddr3_cfg(const struct mx6_ddr_sysinfo *sysinfo,
const struct mx6_mmdc_calibration *calib,
const struct mx6_ddr3_cfg *ddr3_cfg)
@@ -662,6 +952,8 @@ void mx6_dram_cfg(const struct mx6_ddr_sysinfo *sysinfo,
{
if (sysinfo->ddr_type == 0) {
mx6_ddr3_cfg(sysinfo, calib, ddr_cfg);
+ } else if (sysinfo->ddr_type == 1) {
+ mx6_lpddr2_cfg(sysinfo, calib, ddr_cfg);
} else {
puts("Unsupported ddr type\n");
hang();
diff --git a/arch/arm/include/asm/arch-mx6/mx6-ddr.h b/arch/arm/include/asm/arch-mx6/mx6-ddr.h
index e3ba140..fd029af 100644
--- a/arch/arm/include/asm/arch-mx6/mx6-ddr.h
+++ b/arch/arm/include/asm/arch-mx6/mx6-ddr.h
@@ -372,6 +372,21 @@ struct mx6_ddr3_cfg {
u8 SRT; /* self-refresh temperature: 0=normal, 1=extended */
};
+/* Device Information: Varies per LPDDR2 part number and speed grade */
+struct mx6_lpddr2_cfg {
+ u16 mem_speed; /* ie 800 for LPDDR2-800 */
+ u8 density; /* chip density (Gb) (1,2,4,8) */
+ u8 width; /* bus width (bits) (4,8,16) */
+ u8 banks; /* number of banks */
+ u8 rowaddr; /* row address bits (11-16)*/
+ u8 coladdr; /* col address bits (9-12) */
+ u16 trcd_lp;
+ u16 trppb_lp;
+ u16 trpab_lp;
+ u16 trcmin; /* tRC min (ns*100) */
+ u16 trasmin; /* tRAS min (ns*100) */
+};
+
/* System Information: Varies per board design, layout, and term choices */
struct mx6_ddr_sysinfo {
u8 dsize; /* size of bus (in dwords: 0=16bit,1=32bit,2=64bit) */
--
1.8.4
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