mx6: ddr: Allow changing REFSEL and REFR fields

Currently MX6 SPL DDR initialization hardcodes the REF_SEL and
REFR fields of the MDREF register as 1 and 7, respectively for
DDR3 and 0 and 3 for LPDDR2.

Looking at the MDREF initialization done via DCD we see that
boards do need to initialize these fields differently:

$ git grep 0x021b0020 board/
board/bachmann/ot1200/mx6q_4x_mt41j128.cfg:DATA 4 0x021b0020 0x00005800
board/ccv/xpress/imximage.cfg:DATA 4 0x021b0020 0x00000800 /* MMDC0_MDREF */
board/freescale/mx6qarm2/imximage.cfg:DATA 4 0x021b0020 0x7800
board/freescale/mx6qarm2/imximage.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6qarm2/imximage_mx6dl.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6qarm2/imximage_mx6dl.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6qsabreauto/imximage.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6qsabreauto/mx6dl.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6qsabreauto/mx6qp.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6sabresd/mx6dlsabresd.cfg:DATA 4      0x021b0020 0x00005800
board/freescale/mx6sabresd/mx6q_4x_mt41j128.cfg:DATA 4 0x021b0020 0x00005800
board/freescale/mx6slevk/imximage.cfg:DATA 4 0x021b0020 0x00001800
board/freescale/mx6sxsabreauto/imximage.cfg:DATA 4 0x021b0020 0x00000800
board/freescale/mx6sxsabresd/imximage.cfg:DATA 4 0x021b0020 0x00000800
board/warp/imximage.cfg:DATA 4 0x021b0020 0x00001800

So introduce a mechanism for users to be able to configure
REFSEL and REFR fields as needed.

Keep all the mx6 SPL users in their current REF_SEL and REFR values,
so no functional changes for the existing users.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Eric Nelson <eric@nelint.com>

arch/arm/cpu/armv7/mx6/ddr.c

@@ -1166,8 +1166,7 @@ void mx6_lpddr2_cfg(const struct mx6_ddr_sysinfo *sysinfo,
 	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 */
+	mmdc0->mdref = (sysinfo->refsel << 14) | (sysinfo->refr << 11);
 
 	/* Step 13: Deassert config request - init complete */
 	mmdc0->mdscr = 0x00000000;
@@ -1472,8 +1471,7 @@ void mx6_ddr3_cfg(const struct mx6_ddr_sysinfo *sysinfo,
 		MMDC1(mpzqhwctrl, val);
 
 	/* Step 12: Configure and activate periodic refresh */
-	mmdc0->mdref = (1 << 14) | /* REF_SEL: Periodic refresh cycle: 32kHz */
-		       (7 << 11);  /* REFR: Refresh Rate - 8 refreshes */
+	mmdc0->mdref = (sysinfo->refsel << 14) | (sysinfo->refr << 11);
 
 	/* Step 13: Deassert config request - init complete */
 	mmdc0->mdscr = 0x00000000;

arch/arm/include/asm/arch-mx6/mx6-ddr.h

@@ -408,6 +408,8 @@ struct mx6_ddr_sysinfo {
 	u8 sde_to_rst;	/* Time from SDE enable until DDR reset# is high */
 	u8 pd_fast_exit;/* enable precharge powerdown fast-exit */
 	u8 ddr_type;	/* DDR type: DDR3(0) or LPDDR2(1) */
+	u8 refsel;	/* REF_SEL field of register MDREF */
+	u8 refr;	/* REFR field of register MDREF */
 };
 
 /*

board/bachmann/ot1200/ot1200_spl.c

@@ -85,6 +85,8 @@ static struct mx6_ddr_sysinfo ot1200_ddr_sysinfo = {
 	.bi_on      = 1,	/* Bank interleaving enabled */	/* war 1 */
 	.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 	.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
+	.refsel = 1,		/* Refresh cycles at 32KHz */
+	.refr = 7,		/* 8 refresh commands per refresh cycle */
 };
 
 /* MT41K128M16JT-125 */

board/barco/platinum/spl_picon.c

@@ -138,6 +138,8 @@ static void spl_dram_init(int width)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7, 	/* 8 refresh commands per refresh cycle */
 	};
 
 	mx6sdl_dram_iocfg(width, &mx6sdl_ddr_ioregs, &mx6sdl_grp_ioregs);

board/barco/platinum/spl_titanium.c

@@ -141,6 +141,8 @@ static void spl_dram_init(int width)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,		/* Refresh cycles at 32KHz */
+		.refr = 7,		/* 8 refresh commands per refresh cycle */
 	};
 
 	mx6dq_dram_iocfg(width, &mx6dq_ddr_ioregs, &mx6dq_grp_ioregs);

board/ccv/xpress/spl.c

@@ -60,6 +60,8 @@ struct mx6_ddr_sysinfo ddr_sysinfo = {
 	.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 	.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 	.ddr_type = DDR_TYPE_DDR3,
+	.refsel = 1,		/* Refresh cycles at 32KHz */
+	.refr = 7,		/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_ddr3_cfg mem_ddr = {

board/compulab/cm_fx6/spl.c

@@ -107,6 +107,8 @@ static struct mx6_ddr_sysinfo cm_fx6_sysinfo_s = {
 	.mif3_mode	= 3,
 	.rst_to_cke	= 0x23,
 	.sde_to_rst	= 0x10,
+	.refsel = 1,		/* Refresh cycles at 32KHz */
+	.refr = 7,		/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_ddr3_cfg cm_fx6_ddr3_cfg_s = {
@@ -174,6 +176,8 @@ static struct mx6_ddr_sysinfo cm_fx6_sysinfo_q = {
 	.mif3_mode	= 3,
 	.rst_to_cke	= 0x23,
 	.sde_to_rst	= 0x10,
+	.refsel = 1,		/* Refresh cycles at 32KHz */
+	.refr = 7,		/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_ddr3_cfg cm_fx6_ddr3_cfg_q = {

board/congatec/cgtqmx6eval/cgtqmx6eval.c

@@ -1037,6 +1037,8 @@ static void spl_dram_init(int width)
 		.bi_on = 1,
 		.sde_to_rst = 0x0d,
 		.rst_to_cke = 0x20,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	if (is_cpu_type(MXC_CPU_MX6Q) && is_2gb()) {

board/el/el6x/el6x.c

@@ -604,6 +604,8 @@ static void spl_dram_init(void)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	mx6dq_dram_iocfg(64, &mx6_ddr_ioregs, &mx6_grp_ioregs);

board/freescale/mx6sabresd/mx6sabresd.c

@@ -854,6 +854,8 @@ static void spl_dram_init(void)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	if (is_mx6dqp()) {

board/freescale/mx6slevk/mx6slevk.c

@@ -494,6 +494,8 @@ static void spl_dram_init(void)
 		.sde_to_rst = 0,    /* LPDDR2 does not need this field */
 		.rst_to_cke = 0x10, /* JEDEC value for LPDDR2: 200us */
 		.ddr_type = DDR_TYPE_LPDDR2,
+		.refsel = 0,	/* Refresh cycles at 64KHz */
+		.refr = 3,	/* 4 refresh commands per refresh cycle */
 	};
 	mx6sl_dram_iocfg(32, &mx6_ddr_ioregs, &mx6_grp_ioregs);
 	mx6_dram_cfg(&sysinfo, &mx6_mmcd_calib, &mem_ddr);

board/freescale/mx6sxsabresd/mx6sxsabresd.c

@@ -637,6 +637,8 @@ static void spl_dram_init(void)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	mx6sx_dram_iocfg(mem_ddr.width, &mx6_ddr_ioregs, &mx6_grp_ioregs);

board/freescale/mx6ul_14x14_evk/mx6ul_14x14_evk.c

@@ -764,6 +764,8 @@ struct mx6_ddr_sysinfo ddr_sysinfo = {
 	.sde_to_rst = 0,    /* LPDDR2 does not need this field */
 	.rst_to_cke = 0x10, /* JEDEC value for LPDDR2: 200us */
 	.ddr_type = DDR_TYPE_LPDDR2,
+	.refsel = 0,	/* Refresh cycles at 64KHz */
+	.refr = 3,	/* 4 refresh commands per refresh cycle */
 };
 
 #else
@@ -802,6 +804,8 @@ struct mx6_ddr_sysinfo ddr_sysinfo = {
 	.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 	.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 	.ddr_type = DDR_TYPE_DDR3,
+	.refsel = 1,	/* Refresh cycles at 32KHz */
+	.refr = 7,	/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_ddr3_cfg mem_ddr = {

board/gateworks/gw_ventana/gw_ventana_spl.c

@@ -394,6 +394,8 @@ static void spl_dram_init(int width, int size_mb, int board_model)
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.pd_fast_exit = 1, /* enable precharge power-down fast exit */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	/*

board/kosagi/novena/novena_spl.c

@@ -520,6 +520,8 @@ static struct mx6_ddr_sysinfo novena_ddr_info = {
 	.bi_on		= 1,	/* Bank interleaving enabled */
 	.sde_to_rst	= 0x10,	/* 14 cycles, 200us (JEDEC default) */
 	.rst_to_cke	= 0x23,	/* 33 cycles, 500us (JEDEC default) */
+	.refsel = 1,	/* Refresh cycles at 32KHz */
+	.refr = 7,	/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_ddr3_cfg elpida_4gib_1600 = {

board/phytec/pcm058/pcm058.c

@@ -521,6 +521,8 @@ static void spl_dram_init(void)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	mx6dq_dram_iocfg(64, &mx6_ddr_ioregs, &mx6_grp_ioregs);

board/solidrun/mx6cuboxi/mx6cuboxi.c

@@ -605,6 +605,8 @@ static void spl_dram_init(int width)
 		.sde_to_rst = 0x10,	/* 14 cycles, 200us (JEDEC default) */
 		.rst_to_cke = 0x23,	/* 33 cycles, 500us (JEDEC default) */
 		.ddr_type = DDR_TYPE_DDR3,
+		.refsel = 1,	/* Refresh cycles at 32KHz */
+		.refr = 7,	/* 8 refresh commands per refresh cycle */
 	};
 
 	if (is_mx6dq())

board/udoo/udoo_spl.c

@@ -193,6 +193,8 @@ static struct mx6_ddr_sysinfo mem_qdl = {
 	.mif3_mode = 3,
 	.rst_to_cke = 0x23,
 	.sde_to_rst = 0x10,
+	.refsel = 1,	/* Refresh cycles at 32KHz */
+	.refr = 7,	/* 8 refresh commands per refresh cycle */
 };
 
 static void ccgr_init(void)

board/wandboard/spl.c

@@ -187,6 +187,8 @@ static struct mx6_ddr_sysinfo mem_q = {
 	.mif3_mode	= 3,
 	.rst_to_cke	= 0x23,
 	.sde_to_rst	= 0x10,
+	.refsel = 1,	/* Refresh cycles at 32KHz */
+	.refr = 7,	/* 8 refresh commands per refresh cycle */
 };
 
 static struct mx6_mmdc_calibration mx6dl_1g_mmdc_calib = {
@@ -228,6 +230,8 @@ static struct mx6_ddr_sysinfo mem_dl = {
 	.mif3_mode	= 3,
 	.rst_to_cke	= 0x23,
 	.sde_to_rst	= 0x10,
+	.refsel = 1,	/* Refresh cycles at 32KHz */
+	.refr = 7,	/* 8 refresh commands per refresh cycle */
 };
 
 /* DDR 32bit 512MB */
@@ -245,6 +249,8 @@ static struct mx6_ddr_sysinfo mem_s = {
 	.mif3_mode	= 3,
 	.rst_to_cke	= 0x23,
 	.sde_to_rst	= 0x10,
+	.refsel = 1,	/* Refresh cycles at 32KHz */
+	.refr = 7,	/* 8 refresh commands per refresh cycle */
 };
 
 static void ccgr_init(void)