[PATCH] ARM: OMAP: DTS: N950/N9: fix onenand timings

[PATCH] ARM: OMAP: DTS: N950/N9: fix onenand timings

[Aaro Koskinen]

Commit a758f50f10cf ("mtd: onenand: omap2: Configure driver from DT")
started using DT specified timings for GPMC, and as a result the
OneNAND stopped working on N950/N9 as we had wrong values in the DT.
Fix by updating the values to bootloader timings that have been tested
to be working on both Nokia N950 and N9.

Fixes: a758f50f10cf ("mtd: onenand: omap2: Configure driver from DT")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
---
 arch/arm/boot/dts/omap3-n950-n9.dtsi | 42 ++++++++++++++++++----------
 1 file changed, 28 insertions(+), 14 deletions(-)

diff --git a/arch/arm/boot/dts/omap3-n950-n9.dtsi b/arch/arm/boot/dts/omap3-n950-n9.dtsi
index 0d9b85317529..e142e6c70a59 100644
--- a/arch/arm/boot/dts/omap3-n950-n9.dtsi
+++ b/arch/arm/boot/dts/omap3-n950-n9.dtsi
@@ -370,6 +370,19 @@
 		compatible = "ti,omap2-onenand";
 		reg = <0 0 0x20000>;	/* CS0, offset 0, IO size 128K */
 
+		/*
+		 * These timings are based on CONFIG_OMAP_GPMC_DEBUG=y reported
+		 * bootloader set values when booted with v4.19 using both N950
+		 * and N9 devices (OneNAND Manufacturer: Samsung):
+		 *
+		 *   gpmc cs0 before gpmc_cs_program_settings:
+		 *   cs0 GPMC_CS_CONFIG1: 0xfd001202
+		 *   cs0 GPMC_CS_CONFIG2: 0x00181800
+		 *   cs0 GPMC_CS_CONFIG3: 0x00030300
+		 *   cs0 GPMC_CS_CONFIG4: 0x18001804
+		 *   cs0 GPMC_CS_CONFIG5: 0x03171d1d
+		 *   cs0 GPMC_CS_CONFIG6: 0x97080000
+		 */
 		gpmc,sync-read;
 		gpmc,sync-write;
 		gpmc,burst-length = <16>;
@@ -379,26 +392,27 @@
 		gpmc,device-width = <2>;
 		gpmc,mux-add-data = <2>;
 		gpmc,cs-on-ns = <0>;
-		gpmc,cs-rd-off-ns = <87>;
-		gpmc,cs-wr-off-ns = <87>;
+		gpmc,cs-rd-off-ns = <122>;
+		gpmc,cs-wr-off-ns = <122>;
 		gpmc,adv-on-ns = <0>;
-		gpmc,adv-rd-off-ns = <10>;
-		gpmc,adv-wr-off-ns = <10>;
-		gpmc,oe-on-ns = <15>;
-		gpmc,oe-off-ns = <87>;
+		gpmc,adv-rd-off-ns = <15>;
+		gpmc,adv-wr-off-ns = <15>;
+		gpmc,oe-on-ns = <20>;
+		gpmc,oe-off-ns = <122>;
 		gpmc,we-on-ns = <0>;
-		gpmc,we-off-ns = <87>;
-		gpmc,rd-cycle-ns = <112>;
-		gpmc,wr-cycle-ns = <112>;
-		gpmc,access-ns = <81>;
+		gpmc,we-off-ns = <122>;
+		gpmc,rd-cycle-ns = <148>;
+		gpmc,wr-cycle-ns = <148>;
+		gpmc,access-ns = <117>;
 		gpmc,page-burst-access-ns = <15>;
 		gpmc,bus-turnaround-ns = <0>;
 		gpmc,cycle2cycle-delay-ns = <0>;
 		gpmc,wait-monitoring-ns = <0>;
-		gpmc,clk-activation-ns = <5>;
-		gpmc,wr-data-mux-bus-ns = <30>;
-		gpmc,wr-access-ns = <81>;
-		gpmc,sync-clk-ps = <15000>;
+		gpmc,clk-activation-ns = <10>;
+		gpmc,wr-data-mux-bus-ns = <40>;
+		gpmc,wr-access-ns = <117>;
+
+		gpmc,sync-clk-ps = <15000>; /* TBC; Where this value came? */
 
 		/*
 		 * MTD partition table corresponding to Nokia's MeeGo 1.2
-- 
2.17.0

Re: [PATCH] ARM: OMAP: DTS: N950/N9: fix onenand timings

[Tony Lindgren]

* Aaro Koskinen <aaro.koskinen@iki.fi> [181223 10:24]:
> Commit a758f50f10cf ("mtd: onenand: omap2: Configure driver from DT")
> started using DT specified timings for GPMC, and as a result the
> OneNAND stopped working on N950/N9 as we had wrong values in the DT.
> Fix by updating the values to bootloader timings that have been tested
> to be working on both Nokia N950 and N9.
> 
> Fixes: a758f50f10cf ("mtd: onenand: omap2: Configure driver from DT")

Applying into omap-for-v5.0/fixes thanks.

Tony