1 From d7044f06dea839c61a01e6016a4b9dee15543f8d Mon Sep 17 00:00:00 2001
2 From: Phil Elwell <phil@raspberrypi.org>
3 Date: Thu, 30 Jan 2020 09:47:00 +0000
4 Subject: [PATCH] ARM: dts: Add sd_poll_once dtparam to bcm283x/2711
6 The old sdtweak overlay allowed the SD interface to be effectively
7 disabled unless there was a card present at boot time, but that
8 overlay doesn't work on bcm2711 and has largely been replaced by
9 a set of sd_* dtparams (which have the advantage of being board-
12 Add an sd_poll_once dtparam to allow the same functionality on
13 all Raspberry Pi boards.
15 See: https://github.com/raspberrypi/linux/issues/3286
17 Signed-off-by: Phil Elwell <phil@raspberrypi.org>
19 arch/arm/boot/dts/bcm2708-rpi.dtsi | 1 +
20 arch/arm/boot/dts/bcm2711-rpi-4-b.dts | 2 ++
21 arch/arm/boot/dts/overlays/README | 7 +++++++
22 3 files changed, 10 insertions(+)
24 --- a/arch/arm/boot/dts/bcm2708-rpi.dtsi
25 +++ b/arch/arm/boot/dts/bcm2708-rpi.dtsi
27 watchdog = <&watchdog>,"status";
28 random = <&random>,"status";
29 sd_overclock = <&sdhost>,"brcm,overclock-50:0";
30 + sd_poll_once = <&sdhost>,"non-removable?";
31 sd_force_pio = <&sdhost>,"brcm,force-pio?";
32 sd_pio_limit = <&sdhost>,"brcm,pio-limit:0";
33 sd_debug = <&sdhost>,"brcm,debug";
34 --- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
35 +++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
38 eth_led0 = <&phy1>,"led-modes:0";
39 eth_led1 = <&phy1>,"led-modes:4";
41 + sd_poll_once = <&emmc2>, "non-removable?";
44 --- a/arch/arm/boot/dts/overlays/README
45 +++ b/arch/arm/boot/dts/overlays/README
46 @@ -165,6 +165,13 @@ Params:
47 sd_overclock Clock (in MHz) to use when the MMC framework
50 + sd_poll_once Looks for a card once after booting. Useful
51 + for network booting scenarios to avoid the
52 + overhead of continuous polling. N.B. Using
53 + this option restricts the system to using a
54 + single card per boot (or none at all).
57 sd_force_pio Disable DMA support for SD driver (default off)
59 sd_pio_limit Number of blocks above which to use DMA for