rk3399: dram: making phy into dll bypass mode at low frequency

when dram frequency below 260MHz, phy master dll may unlock, so
let phy master dll working at dll bypass mode when frequency is
below 260MHz.
Signed-off-by: Lin Huang <hl@rock-chips.com>

plat/rockchip/rk3399/drivers/dram/dfs.c

@@ -40,25 +40,17 @@
 
 #include <delay_timer.h>
 
-#define CTL_TRAINING	(1)
-#define PI_TRAINING		(!CTL_TRAINING)
-
-#define EN_READ_GATE_TRAINING	(1)
-#define EN_CA_TRAINING		(0)
-#define EN_WRITE_LEVELING	(0)
-#define EN_READ_LEVELING	(0)
-#define EN_WDQ_LEVELING	(0)
-
 #define ENPER_CS_TRAINING_FREQ	(933)
+#define PHY_DLL_BYPASS_FREQ	(260)
 
 struct pll_div {
-	unsigned int mhz;
-	unsigned int refdiv;
-	unsigned int fbdiv;
-	unsigned int postdiv1;
-	unsigned int postdiv2;
-	unsigned int frac;
-	unsigned int freq;
+	uint32_t mhz;
+	uint32_t refdiv;
+	uint32_t fbdiv;
+	uint32_t postdiv1;
+	uint32_t postdiv2;
+	uint32_t frac;
+	uint32_t freq;
 };
 
 static const struct pll_div dpll_rates_table[] = {
@@ -84,6 +76,7 @@ struct rk3399_dram_status {
 };
 
 static struct rk3399_dram_status rk3399_dram_status;
+static uint32_t wrdqs_delay_val[2][2][4];
 
 static struct rk3399_sdram_default_config ddr3_default_config = {
 	.bl = 8,
@@ -1028,6 +1021,21 @@ static void gen_rk3399_ctl_params_f1(struct timing_related_config
 	}
 }
 
+static void gen_rk3399_enable_training(uint32_t ch_cnt, uint32_t nmhz)
+{
+		uint32_t i, tmp;
+
+		if (nmhz <= PHY_DLL_BYPASS_FREQ)
+			tmp = 0;
+		else
+			tmp = 1;
+
+		for (i = 0; i < ch_cnt; i++) {
+			mmio_clrsetbits_32(CTL_REG(i, 305), 1 << 16, tmp << 16);
+			mmio_clrsetbits_32(CTL_REG(i, 71), 1, tmp);
+		}
+}
+
 static void gen_rk3399_ctl_params(struct timing_related_config *timing_config,
 				  struct dram_timing_t *pdram_timing,
 				  uint32_t fn)
@@ -1036,35 +1044,6 @@ static void gen_rk3399_ctl_params(struct timing_related_config *timing_config,
 		gen_rk3399_ctl_params_f0(timing_config, pdram_timing);
 	else
 		gen_rk3399_ctl_params_f1(timing_config, pdram_timing);
-
-#if CTL_TRAINING
-	uint32_t i, tmp0, tmp1;
-
-	tmp0 = tmp1 = 0;
-#if EN_READ_GATE_TRAINING
-	tmp1 = 1;
-#endif
-
-#if EN_CA_TRAINING
-	tmp0 |= (1 << 8);
-#endif
-
-#if EN_WRITE_LEVELING
-	tmp0 |= (1 << 16);
-#endif
-
-#if EN_READ_LEVELING
-	tmp0 |= (1 << 24);
-#endif
-	for (i = 0; i < timing_config->ch_cnt; i++) {
-		if (tmp0 | tmp1)
-			mmio_setbits_32(CTL_REG(i, 305), 1 << 16);
-		if (tmp0)
-			mmio_setbits_32(CTL_REG(i, 70), tmp0);
-		if (tmp1)
-			mmio_setbits_32(CTL_REG(i, 71), tmp1);
-	}
-#endif
 }
 
 static void gen_rk3399_pi_params_f0(struct timing_related_config *timing_config,
@@ -1432,32 +1411,6 @@ static void gen_rk3399_pi_params(struct timing_related_config *timing_config,
 		gen_rk3399_pi_params_f0(timing_config, pdram_timing);
 	else
 		gen_rk3399_pi_params_f1(timing_config, pdram_timing);
-
-#if PI_TRAINING
-	uint32_t i;
-
-	for (i = 0; i < timing_config->ch_cnt; i++) {
-#if EN_READ_GATE_TRAINING
-		mmio_clrsetbits_32(PI_REG(i, 80), 3 << 24, 2 << 24);
-#endif
-
-#if EN_CA_TRAINING
-		mmio_clrsetbits_32(PI_REG(i, 100), 3 << 8, 2 << 8);
-#endif
-
-#if EN_WRITE_LEVELING
-		mmio_clrsetbits_32(PI_REG(i, 60), 3 << 8, 2 << 8);
-#endif
-
-#if EN_READ_LEVELING
-		mmio_clrsetbits_32(PI_REG(i, 80), 3 << 16, 2 << 16);
-#endif
-
-#if EN_WDQ_LEVELING
-		mmio_clrsetbits_32(PI_REG(i, 124), 3 << 16, 2 << 16);
-#endif
-	}
-#endif
 }
 
 static void gen_rk3399_set_odt(uint32_t odt_en)
@@ -1479,6 +1432,94 @@ static void gen_rk3399_set_odt(uint32_t odt_en)
 	}
 }
 
+static void gen_rk3399_phy_dll_bypass(uint32_t mhz, uint32_t ch,
+		uint32_t index, uint32_t dram_type)
+{
+	uint32_t sw_master_mode = 0;
+	uint32_t rddqs_gate_delay, rddqs_latency, total_delay;
+	uint32_t i;
+
+	if (dram_type == DDR3)
+		total_delay = PI_PAD_DELAY_PS_VALUE;
+	else if (dram_type == LPDDR3)
+		total_delay = PI_PAD_DELAY_PS_VALUE + 2500;
+	else
+		total_delay = PI_PAD_DELAY_PS_VALUE + 1500;
+	/* total_delay + 0.55tck */
+	total_delay +=  (55 * 10000)/mhz;
+	rddqs_latency = total_delay * mhz / 1000000;
+	total_delay -= rddqs_latency * 1000000 / mhz;
+	rddqs_gate_delay = total_delay * 0x200 * mhz / 1000000;
+	if (mhz <= PHY_DLL_BYPASS_FREQ) {
+		sw_master_mode = 0xc;
+		mmio_setbits_32(PHY_REG(ch, 514), 1);
+		mmio_setbits_32(PHY_REG(ch, 642), 1);
+		mmio_setbits_32(PHY_REG(ch, 770), 1);
+
+		/* setting bypass mode slave delay */
+		for (i = 0; i < 4; i++) {
+			/* wr dq delay = -180deg + (0x60 / 4) * 20ps */
+			mmio_clrsetbits_32(PHY_REG(ch, 1 + 128 * i), 0x7ff << 8,
+					   0x4a0 << 8);
+			/* rd dqs/dq delay = (0x60 / 4) * 20ps */
+			mmio_clrsetbits_32(PHY_REG(ch, 11 + 128 * i), 0x3ff,
+					   0xa0);
+			/* rd rddqs_gate delay */
+			mmio_clrsetbits_32(PHY_REG(ch, 2 + 128 * i), 0x3ff,
+					   rddqs_gate_delay);
+			mmio_clrsetbits_32(PHY_REG(ch, 78 + 128 * i), 0xf,
+					   rddqs_latency);
+		}
+		for (i = 0; i < 3; i++)
+			/* adr delay */
+			mmio_clrsetbits_32(PHY_REG(ch, 513 + 128 * i),
+					   0x7ff << 16, 0x80 << 16);
+
+		if ((mmio_read_32(PHY_REG(ch, 86)) & 0xc00) == 0) {
+			/*
+			 * old status is normal mode,
+			 * and saving the wrdqs slave delay
+			 */
+			for (i = 0; i < 4; i++) {
+				/* save and clear wr dqs slave delay */
+				wrdqs_delay_val[ch][index][i] = 0x3ff &
+					(mmio_read_32(PHY_REG(ch, 63 + i * 128))
+					>> 16);
+				mmio_clrsetbits_32(PHY_REG(ch, 63 + i * 128),
+						   0x03ff << 16, 0 << 16);
+				/*
+				 * in normal mode the cmd may delay 1cycle by
+				 * wrlvl and in bypass mode making dqs also
+				 * delay 1cycle.
+				 */
+				mmio_clrsetbits_32(PHY_REG(ch, 78 + i * 128),
+						   0x07 << 8, 0x1 << 8);
+			}
+		}
+	} else if (mmio_read_32(PHY_REG(ch, 86)) & 0xc00) {
+		/* old status is bypass mode and restore wrlvl resume */
+		for (i = 0; i < 4; i++) {
+			mmio_clrsetbits_32(PHY_REG(ch, 63 + i * 128),
+					   0x03ff << 16,
+					   (wrdqs_delay_val[ch][index][i] &
+					    0x3ff) << 16);
+			/* resume phy_write_path_lat_add */
+			mmio_clrbits_32(PHY_REG(ch, 78 + i * 128), 0x07 << 8);
+		}
+	}
+
+	/* phy_sw_master_mode_X PHY_86/214/342/470 4bits offset_8 */
+	mmio_clrsetbits_32(PHY_REG(ch, 86), 0xf << 8, sw_master_mode << 8);
+	mmio_clrsetbits_32(PHY_REG(ch, 214), 0xf << 8, sw_master_mode << 8);
+	mmio_clrsetbits_32(PHY_REG(ch, 342), 0xf << 8, sw_master_mode << 8);
+	mmio_clrsetbits_32(PHY_REG(ch, 470), 0xf << 8, sw_master_mode << 8);
+
+	/* phy_adrctl_sw_master_mode PHY_547/675/803 4bits offset_16 */
+	mmio_clrsetbits_32(PHY_REG(ch, 547), 0xf << 16, sw_master_mode << 16);
+	mmio_clrsetbits_32(PHY_REG(ch, 675), 0xf << 16, sw_master_mode << 16);
+	mmio_clrsetbits_32(PHY_REG(ch, 803), 0xf << 16, sw_master_mode << 16);
+}
+
 static void gen_rk3399_phy_params(struct timing_related_config *timing_config,
 				  struct drv_odt_lp_config *drv_config,
 				  struct dram_timing_t *pdram_timing,
@@ -1586,12 +1627,6 @@ static void gen_rk3399_phy_params(struct timing_related_config *timing_config,
 		gate_delay_ps = delay_frac_ps + 1000 - (trpre_min_ps / 2);
 		gate_delay_frac_ps = gate_delay_ps % 1000;
 		tmp = gate_delay_frac_ps * 0x200 / 1000;
-		/* PHY_RDDQS_GATE_BYPASS_SLAVE_DELAY */
-		/* DENALI_PHY_2/130/258/386 10bits offset_0 */
-		mmio_clrsetbits_32(PHY_REG(i, 2), 0x2ff, tmp);
-		mmio_clrsetbits_32(PHY_REG(i, 130), 0x2ff, tmp);
-		mmio_clrsetbits_32(PHY_REG(i, 258), 0x2ff, tmp);
-		mmio_clrsetbits_32(PHY_REG(i, 386), 0x2ff, tmp);
 		/* PHY_RDDQS_GATE_SLAVE_DELAY */
 		/* DENALI_PHY_77/205/333/461 10bits offset_16 */
 		mmio_clrsetbits_32(PHY_REG(i, 77), 0x2ff << 16, tmp << 16);
@@ -1606,12 +1641,6 @@ static void gen_rk3399_phy_params(struct timing_related_config *timing_config,
 		mmio_clrsetbits_32(PHY_REG(i, 138), 0xf, tmp);
 		mmio_clrsetbits_32(PHY_REG(i, 266), 0xf, tmp);
 		mmio_clrsetbits_32(PHY_REG(i, 394), 0xf, tmp);
-		/* PHY_RDDQS_LATENCY_ADJUST */
-		/* DENALI_PHY_78/206/334/462 4bits offset_0 */
-		mmio_clrsetbits_32(PHY_REG(i, 78), 0xf, tmp);
-		mmio_clrsetbits_32(PHY_REG(i, 206), 0xf, tmp);
-		mmio_clrsetbits_32(PHY_REG(i, 334), 0xf, tmp);
-		mmio_clrsetbits_32(PHY_REG(i, 462), 0xf, tmp);
 		/* PHY_GTLVL_LAT_ADJ_START */
 		/* DENALI_PHY_80/208/336/464 4bits offset_16 */
 		tmp = delay_frac_ps / 1000;
@@ -1696,6 +1725,8 @@ static void gen_rk3399_phy_params(struct timing_related_config *timing_config,
 			mmio_setbits_32(PHY_REG(i, 340), 0x1 << 16);
 			mmio_setbits_32(PHY_REG(i, 468), 0x1 << 16);
 		}
+		gen_rk3399_phy_dll_bypass(pdram_timing->mhz, i, fn,
+					  timing_config->dram_type);
 	}
 }
 
@@ -2018,6 +2049,8 @@ static uint32_t prepare_ddr_timing(uint32_t mhz)
 	rk3399_dram_status.index_freq[index] = mhz;
 
 out:
+	gen_rk3399_enable_training(rk3399_dram_status.timing_config.ch_cnt,
+				   mhz);
 	return index;
 }