[U-Boot] [PATCH 3/4] ARM: dts: am57xx: Disable voltage switching for SD card

Faiz Abbas faiz_abbas at ti.com
Thu Jun 20 09:37:21 UTC 2019


If UHS speed modes are enabled, a compatible SD card switches down to 1.8V
during enumeration. If after this a software reboot/crash takes place and
on-chip ROM tries to enumerate the SD card, the difference in
IO voltages (host @ 3.3V and card @ 1.8V) may end up damaging the card.

The fix for this is to have support for power cycling the card in
hardware (with a PORz/soft-reset line causing a power cycle of the card).
Because the beaglebone X15 (rev A,B and C), am57xx-evms and am57xx-idks don't
have this capability, disable voltage switching for these boards.

The major effect of this is that the maximum supported speed mode is now
high speed(50 MHz) down from SDR104(200 MHz).

Signed-off-by: Faiz Abbas <faiz_abbas at ti.com>
---
 arch/arm/dts/am571x-idk.dts                | 7 +------
 arch/arm/dts/am572x-idk.dts                | 7 +------
 arch/arm/dts/am57xx-beagle-x15-common.dtsi | 1 +
 arch/arm/dts/am57xx-beagle-x15-revb1.dts   | 7 +------
 arch/arm/dts/am57xx-beagle-x15-revc.dts    | 7 +------
 arch/arm/dts/am57xx-idk-common.dtsi        | 1 +
 6 files changed, 6 insertions(+), 24 deletions(-)

diff --git a/arch/arm/dts/am571x-idk.dts b/arch/arm/dts/am571x-idk.dts
index eb5fda81f5..798fbfe19d 100644
--- a/arch/arm/dts/am571x-idk.dts
+++ b/arch/arm/dts/am571x-idk.dts
@@ -102,14 +102,9 @@
 };
 
 &mmc1 {
-	pinctrl-names = "default", "hs", "sdr12", "sdr25", "sdr50", "ddr50", "sdr104";
+	pinctrl-names = "default", "hs";
 	pinctrl-0 = <&mmc1_pins_default_no_clk_pu>;
 	pinctrl-1 = <&mmc1_pins_hs>;
-	pinctrl-2 = <&mmc1_pins_sdr12>;
-	pinctrl-3 = <&mmc1_pins_sdr25>;
-	pinctrl-4 = <&mmc1_pins_sdr50>;
-	pinctrl-5 = <&mmc1_pins_ddr50_rev20 &mmc1_iodelay_ddr50_conf>;
-	pinctrl-6 = <&mmc1_pins_sdr104 &mmc1_iodelay_sdr104_rev20_conf>;
 };
 
 &mmc2 {
diff --git a/arch/arm/dts/am572x-idk.dts b/arch/arm/dts/am572x-idk.dts
index 2247948553..42e88c1bc0 100644
--- a/arch/arm/dts/am572x-idk.dts
+++ b/arch/arm/dts/am572x-idk.dts
@@ -21,14 +21,9 @@
 };
 
 &mmc1 {
-	pinctrl-names = "default", "hs", "sdr12", "sdr25", "sdr50", "ddr50", "sdr104";
+	pinctrl-names = "default", "hs";
 	pinctrl-0 = <&mmc1_pins_default_no_clk_pu>;
 	pinctrl-1 = <&mmc1_pins_hs>;
-	pinctrl-2 = <&mmc1_pins_sdr12>;
-	pinctrl-3 = <&mmc1_pins_sdr25>;
-	pinctrl-4 = <&mmc1_pins_sdr50>;
-	pinctrl-5 = <&mmc1_pins_ddr50 &mmc1_iodelay_ddr_rev20_conf>;
-	pinctrl-6 = <&mmc1_pins_sdr104 &mmc1_iodelay_sdr104_rev20_conf>;
 };
 
 &mmc2 {
diff --git a/arch/arm/dts/am57xx-beagle-x15-common.dtsi b/arch/arm/dts/am57xx-beagle-x15-common.dtsi
index 49aeecd312..d6b94d528f 100644
--- a/arch/arm/dts/am57xx-beagle-x15-common.dtsi
+++ b/arch/arm/dts/am57xx-beagle-x15-common.dtsi
@@ -433,6 +433,7 @@
 
 	bus-width = <4>;
 	cd-gpios = <&gpio6 27 GPIO_ACTIVE_LOW>; /* gpio 219 */
+	no-1-8-v;
 };
 
 &mmc2 {
diff --git a/arch/arm/dts/am57xx-beagle-x15-revb1.dts b/arch/arm/dts/am57xx-beagle-x15-revb1.dts
index 5a77b33492..34c6996582 100644
--- a/arch/arm/dts/am57xx-beagle-x15-revb1.dts
+++ b/arch/arm/dts/am57xx-beagle-x15-revb1.dts
@@ -19,14 +19,9 @@
 };
 
 &mmc1 {
-	pinctrl-names = "default", "hs", "sdr12", "sdr25", "sdr50", "ddr50", "sdr104";
+	pinctrl-names = "default", "hs";
 	pinctrl-0 = <&mmc1_pins_default>;
 	pinctrl-1 = <&mmc1_pins_hs>;
-	pinctrl-2 = <&mmc1_pins_sdr12>;
-	pinctrl-3 = <&mmc1_pins_sdr25>;
-	pinctrl-4 = <&mmc1_pins_sdr50>;
-	pinctrl-5 = <&mmc1_pins_ddr50 &mmc1_iodelay_ddr_rev11_conf>;
-	pinctrl-6 = <&mmc1_pins_sdr104 &mmc1_iodelay_sdr104_rev11_conf>;
 	vmmc-supply = <&vdd_3v3>;
 	vqmmc-supply = <&ldo1_reg>;
 };
diff --git a/arch/arm/dts/am57xx-beagle-x15-revc.dts b/arch/arm/dts/am57xx-beagle-x15-revc.dts
index 17c41da3b5..ccd99160bb 100644
--- a/arch/arm/dts/am57xx-beagle-x15-revc.dts
+++ b/arch/arm/dts/am57xx-beagle-x15-revc.dts
@@ -19,14 +19,9 @@
 };
 
 &mmc1 {
-	pinctrl-names = "default", "hs", "sdr12", "sdr25", "sdr50", "ddr50", "sdr104";
+	pinctrl-names = "default", "hs";
 	pinctrl-0 = <&mmc1_pins_default>;
 	pinctrl-1 = <&mmc1_pins_hs>;
-	pinctrl-2 = <&mmc1_pins_sdr12>;
-	pinctrl-3 = <&mmc1_pins_sdr25>;
-	pinctrl-4 = <&mmc1_pins_sdr50>;
-	pinctrl-5 = <&mmc1_pins_ddr50 &mmc1_iodelay_ddr_rev20_conf>;
-	pinctrl-6 = <&mmc1_pins_sdr104 &mmc1_iodelay_sdr104_rev20_conf>;
 	vmmc-supply = <&vdd_3v3>;
 	vqmmc-supply = <&ldo1_reg>;
 };
diff --git a/arch/arm/dts/am57xx-idk-common.dtsi b/arch/arm/dts/am57xx-idk-common.dtsi
index fa5a078b27..fdb4e0e47c 100644
--- a/arch/arm/dts/am57xx-idk-common.dtsi
+++ b/arch/arm/dts/am57xx-idk-common.dtsi
@@ -405,6 +405,7 @@
 	vqmmc-supply = <&ldo1_reg>;
 	bus-width = <4>;
 	cd-gpios = <&gpio6 27 GPIO_ACTIVE_LOW>; /* gpio 219 */
+	no-1-8-v;
 };
 
 &mmc2 {
-- 
2.19.2



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