[U-Boot] [PATCH v2 2/3] omap4: make SDRAM init work for ES1.0 silicon

[Aneesh V]

SDRAM init was not working on ES1.0 due to a programming
error. A pointer that was passed by value to a function
was set in function emif_get_device_details(), but the effect
wouldn't be seen in the calling function. The issue came
out while testing for ES1.0 because ES1.0 doesn't have any
SDRAM chips connected to CS1

Signed-off-by: Aneesh V <aneesh at ti.com>
---
V2:
* Rebased on latest HEAD of u-boot-ti master
---
 arch/arm/cpu/armv7/omap4/emif.c         |   47 +++++-------------------------
 arch/arm/cpu/armv7/omap4/sdram_elpida.c |   24 ++++++++--------
 arch/arm/include/asm/arch-omap4/emif.h  |    5 +--
 3 files changed, 22 insertions(+), 54 deletions(-)

diff --git a/arch/arm/cpu/armv7/omap4/emif.c b/arch/arm/cpu/armv7/omap4/emif.c
index 487ec42..8c46464 100644
--- a/arch/arm/cpu/armv7/omap4/emif.c
+++ b/arch/arm/cpu/armv7/omap4/emif.c
@@ -963,10 +963,11 @@ static u8 is_lpddr2_sdram_present(u32 base, u32 cs,
 	return 1;
 }
 
-static struct lpddr2_device_details *get_lpddr2_details(u32 base, u8 cs,
+struct lpddr2_device_details *emif_get_device_details(u32 emif_nr, u8 cs,
 			struct lpddr2_device_details *lpddr2_dev_details)
 {
 	u32 phy;
+	u32 base = (emif_nr == 1) ? OMAP44XX_EMIF1 : OMAP44XX_EMIF2;
 	struct emif_reg_struct *emif = (struct emif_reg_struct *)base;
 
 	if (!lpddr2_dev_details)
@@ -985,40 +986,6 @@ static struct lpddr2_device_details *get_lpddr2_details(u32 base, u8 cs,
 
 	return lpddr2_dev_details;
 }
-
-void emif_get_device_details(u32 emif_nr,
-		struct lpddr2_device_details *cs0_device_details,
-		struct lpddr2_device_details *cs1_device_details)
-{
-	u32 base = (emif_nr == 1) ? OMAP44XX_EMIF1 : OMAP44XX_EMIF2;
-
-	if (running_from_sdram()) {
-		/*
-		 * We can not do automatic discovery running from SDRAM
-		 * Most likely we came here by mistake. Indicate error
-		 * by returning NULL
-		 */
-		cs0_device_details = NULL;
-		cs1_device_details = NULL;
-	} else {
-		/*
-		 * Automatically find the device details:
-		 *
-		 * Reset the PHY after each call to get_lpddr2_details().
-		 * If there is nothing connected to a given chip select
-		 * (typically CS1) mode register reads will mess up with
-		 * the PHY state and subsequent initialization won't work.
-		 * PHY reset brings back PHY to a good state.
-		 */
-		cs0_device_details =
-		    get_lpddr2_details(base, CS0, cs0_device_details);
-		emif_reset_phy(base);
-
-		cs1_device_details =
-		    get_lpddr2_details(base, CS1, cs1_device_details);
-		emif_reset_phy(base);
-	}
-}
 #endif /* CONFIG_SYS_AUTOMATIC_SDRAM_DETECTION */
 
 static void do_sdram_init(u32 base)
@@ -1051,10 +1018,12 @@ static void do_sdram_init(u32 base)
 	 * - Obtained from user otherwise
 	 */
 	struct lpddr2_device_details cs0_dev_details, cs1_dev_details;
-	emif_get_device_details(emif_nr, &cs0_dev_details,
-				&cs1_dev_details);
-	dev_details.cs0_device_details = &cs0_dev_details;
-	dev_details.cs1_device_details = &cs1_dev_details;
+	emif_reset_phy(base);
+	dev_details.cs0_device_details = emif_get_device_details(base, CS0,
+						&cs0_dev_details);
+	dev_details.cs1_device_details = emif_get_device_details(base, CS1,
+						&cs1_dev_details);
+	emif_reset_phy(base);
 
 	/* Return if no devices on this EMIF */
 	if (!dev_details.cs0_device_details &&
diff --git a/arch/arm/cpu/armv7/omap4/sdram_elpida.c b/arch/arm/cpu/armv7/omap4/sdram_elpida.c
index 7757aad..edc5326 100644
--- a/arch/arm/cpu/armv7/omap4/sdram_elpida.c
+++ b/arch/arm/cpu/armv7/omap4/sdram_elpida.c
@@ -141,24 +141,24 @@ static const struct lpddr2_device_details elpida_2G_S4_details = {
 	.manufacturer	= LPDDR2_MANUFACTURER_ELPIDA
 };
 
-static void emif_get_device_details_sdp(u32 emif_nr,
-		struct lpddr2_device_details *cs0_device_details,
-		struct lpddr2_device_details *cs1_device_details)
+struct lpddr2_device_details *emif_get_device_details_sdp(u32 emif_nr, u8 cs,
+			struct lpddr2_device_details *lpddr2_dev_details)
 {
 	u32 omap_rev = omap_revision();
 
 	/* EMIF1 & EMIF2 have identical configuration */
-	*cs0_device_details = elpida_2G_S4_details;
-
-	if (omap_rev == OMAP4430_ES1_0)
-		cs1_device_details = NULL;
-	else
-		*cs1_device_details = elpida_2G_S4_details;
+	if ((omap_rev == OMAP4430_ES1_0) && (cs == CS1)) {
+		/* Nothing connected on CS1 for ES1.0 */
+		return NULL;
+	} else {
+		/* In all other cases Elpida 2G device */
+		*lpddr2_dev_details = elpida_2G_S4_details;
+		return lpddr2_dev_details;
+	}
 }
 
-void emif_get_device_details(u32 emif_nr,
-		struct lpddr2_device_details *cs0_device_details,
-		struct lpddr2_device_details *cs1_device_details)
+struct lpddr2_device_details *emif_get_device_details(u32 emif_nr, u8 cs,
+			struct lpddr2_device_details *lpddr2_dev_details)
 	__attribute__((weak, alias("emif_get_device_details_sdp")));
 
 #endif /* CONFIG_SYS_EMIF_PRECALCULATED_TIMING_REGS */
diff --git a/arch/arm/include/asm/arch-omap4/emif.h b/arch/arm/include/asm/arch-omap4/emif.h
index 37ad1fd..6845c65 100644
--- a/arch/arm/include/asm/arch-omap4/emif.h
+++ b/arch/arm/include/asm/arch-omap4/emif.h
@@ -1029,9 +1029,8 @@ struct emif_regs {
 void emif_get_reg_dump(u32 emif_nr, const struct emif_regs **regs);
 void emif_get_dmm_regs(const struct dmm_lisa_map_regs **dmm_lisa_regs);
 #else
-void emif_get_device_details(u32 emif_nr,
-		struct lpddr2_device_details *cs0_device_details,
-		struct lpddr2_device_details *cs1_device_details);
+struct lpddr2_device_details *emif_get_device_details(u32 emif_nr, u8 cs,
+			struct lpddr2_device_details *lpddr2_dev_details);
 void emif_get_device_timings(u32 emif_nr,
 		const struct lpddr2_device_timings **cs0_device_timings,
 		const struct lpddr2_device_timings **cs1_device_timings);
-- 
1.7.0.4