rockchip/rk3399: reset system if DDR init fails

We found sdram may fail in pctl_cfg(), so we check the status in this
function. If it exceeds 100ms still in this function, we will restart
the system. We also found there are rare chances DDR training fails,
so also restart system in that case.

BUG=chrome-os-partner:57988
BRANCH=None
TEST=coreboot resets on failure and eventually the system comes up

Change-Id: Icc0688da028a8f4f81eafe36bbaa79fdf2bcea74
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 89e45f8352f62e19a203316330aba14ccc5c8b11
Original-Change-Id: If4e78983abcfdfe1e0e26847448d86169e598700
Original-Signed-off-by: Lin Huang <hl@rock-chips.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/397439
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/17045
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

2 files changed, 28 insertions, 11 deletions

diff --git a/src/mainboard/google/gru/Makefile.inc b/src/mainboard/google/gru/Makefile.inc
index 034edde8a7..122139dd15 100644
--- a/src/mainboard/google/gru/Makefile.inc
+++ b/src/mainboard/google/gru/Makefile.inc
@@ -31,6 +31,7 @@ romstage-y += chromeos.c
 romstage-y += memlayout.ld
 romstage-y += pwm_regulator.c
 romstage-y += romstage.c
+romstage-y += reset.c
 romstage-y += sdram_configs.c
 
 ramstage-y += boardid.c
diff --git a/src/soc/rockchip/rk3399/sdram.c b/src/soc/rockchip/rk3399/sdram.c
index ed13a82d38..ee980339a1 100644
--- a/src/soc/rockchip/rk3399/sdram.c
+++ b/src/soc/rockchip/rk3399/sdram.c
@@ -16,12 +16,14 @@
 #include <arch/io.h>
 #include <console/console.h>
 #include <delay.h>
+#include <reset.h>
 #include <soc/addressmap.h>
 #include <soc/clock.h>
 #include <soc/sdram.h>
 #include <soc/grf.h>
 #include <soc/soc.h>
 #include <string.h>
+#include <timer.h>
 #include <types.h>
 
 #define DDR_PI_OFFSET			0x800
@@ -466,8 +468,8 @@ static void phy_io_config(u32 channel,
 	clrsetbits_le32(&denali_phy[939], 0x3 << 17, speed << 17);
 }
 
-static void pctl_cfg(u32 channel,
-		     const struct rk3399_sdram_params *sdram_params)
+static int pctl_cfg(u32 channel,
+		    const struct rk3399_sdram_params *sdram_params)
 {
 	u32 *denali_ctl = rk3399_ddr_pctl[channel]->denali_ctl;
 	u32 *denali_pi = rk3399_ddr_pi[channel]->denali_pi;
@@ -476,6 +478,7 @@ static void pctl_cfg(u32 channel,
 	const u32 *params_phy = sdram_params->phy_regs.denali_phy;
 	u32 tmp, tmp1, tmp2;
 	u32 pwrup_srefresh_exit;
+	struct stopwatch sw;
 
 	/*
 	 * work around controller bug:
@@ -554,14 +557,16 @@ static void pctl_cfg(u32 channel,
 	/* PHY_DLL_RST_EN */
 	clrsetbits_le32(&denali_phy[957], 0x3 << 24, 0x2 << 24);
 
-	/*
-	 * FIXME:
-	 * need to care ERROR bit
-	 */
-	while (!(read32(&denali_ctl[203]) & (1 << 3)))
-		;
+	/* FIXME: need to care ERROR bit */
+	stopwatch_init_msecs_expire(&sw, 100);
+	while (!(read32(&denali_ctl[203]) & (1 << 3))) {
+		if (stopwatch_expired(&sw))
+			return -1;
+	}
+
 	clrsetbits_le32(&denali_ctl[68], PWRUP_SREFRESH_EXIT,
 			pwrup_srefresh_exit);
+	return 0;
 }
 
 static void select_per_cs_training_index(u32 channel, u32 rank)
@@ -987,14 +992,25 @@ void sdram_init(const struct rk3399_sdram_params *sdram_params)
 		if (channel >= sdram_params->num_channels)
 			continue;
 
-		pctl_cfg(channel, sdram_params);
+		/*
+		 * TODO: we need to find the root cause why this
+		 * step may fail, before that, we just reset the
+		 * system, and start again.
+		 */
+		if (pctl_cfg(channel, sdram_params) != 0) {
+			printk(BIOS_ERR, "pctl_cfg fail, reset\n");
+			hard_reset();
+		}
 
 		/* LPDDR2/LPDDR3 need to wait DAI complete, max 10us */
 		if (dramtype == LPDDR3)
 			udelay(10);
 
-		if (data_training(channel, sdram_params, PI_FULL_TARINING))
-			die("SDRAM initialization failed!");
+		if (data_training(channel, sdram_params, PI_FULL_TARINING)) {
+			printk(BIOS_ERR,
+			       "SDRAM initialization failed, reset\n");
+			hard_reset();
+		}
 
 		set_ddrconfig(sdram_params, channel,
 			      sdram_params->ch[channel].ddrconfig);