From: Philipp Tomsich Date: Tue, 28 Nov 2017 16:56:11 +0000 (+0100) Subject: rockchip: rk3399-puma: add code to allow forcing a power-on reset X-Git-Tag: v2018.01-rc1~25^2~3 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=ae0d33a7291a164a11ae034bcf4f71226b2bef48;p=u-boot rockchip: rk3399-puma: add code to allow forcing a power-on reset The reset circuitry in the RK3399 only resets 'almost all logic' when a software reset is performed. To make our software maintenance easier in the future, we want to have the option (controlled by a DTS property) to force all reset causes other than a power-on reset to trigger a power-on reset via a GPIO trigger. This adds the necessary support to the rk3399-puma (i.e. RK3399-Q7) board-support and the documentation for the new property (sysreset-gpio) within the /config-node. Signed-off-by: Philipp Tomsich Tested-by: Klaus Goger Reviewed-by: Simon Glass --- diff --git a/board/theobroma-systems/puma_rk3399/puma-rk3399.c b/board/theobroma-systems/puma_rk3399/puma-rk3399.c index 7f2dd65d44..0ad267cdd0 100644 --- a/board/theobroma-systems/puma_rk3399/puma-rk3399.c +++ b/board/theobroma-systems/puma_rk3399/puma-rk3399.c @@ -11,7 +11,10 @@ #include #include #include +#include #include +#include +#include #include #include #include @@ -33,9 +36,50 @@ int board_init(void) return 0; } +static void rk3399_force_power_on_reset(void) +{ + ofnode node; + struct gpio_desc sysreset_gpio; + + debug("%s: trying to force a power-on reset\n", __func__); + + node = ofnode_path("/config"); + if (!ofnode_valid(node)) { + debug("%s: no /config node?\n", __func__); + return; + } + + if (gpio_request_by_name_nodev(node, "sysreset-gpio", 0, + &sysreset_gpio, GPIOD_IS_OUT)) { + debug("%s: could not find a /config/sysreset-gpio\n", __func__); + return; + } + + dm_gpio_set_value(&sysreset_gpio, 1); +} + void spl_board_init(void) { int ret; + struct rk3399_cru *cru = rockchip_get_cru(); + + /* + * The RK3399 resets only 'almost all logic' (see also in the TRM + * "3.9.4 Global software reset"), when issuing a software reset. + * This may cause issues during boot-up for some configurations of + * the application software stack. + * + * To work around this, we test whether the last reset reason was + * a power-on reset and (if not) issue an overtemp-reset to reset + * the entire module. + * + * While this was previously fixed by modifying the various places + * that could generate a software reset (e.g. U-Boot's sysreset + * driver, the ATF or Linux), we now have it here to ensure that + * we no longer have to track this through the various components. + */ + if (cru->glb_rst_st != 0) + rk3399_force_power_on_reset(); /* * Turning the eMMC and SPI back on (if disabled via the Qseven diff --git a/doc/device-tree-bindings/config.txt b/doc/device-tree-bindings/config.txt index 15e4349c19..6cdc16da5b 100644 --- a/doc/device-tree-bindings/config.txt +++ b/doc/device-tree-bindings/config.txt @@ -46,3 +46,9 @@ u-boot,spl-payload-offset If present (and SPL is controlled by the device-tree), this allows to override the CONFIG_SYS_SPI_U_BOOT_OFFS setting using a value from the device-tree. + +sysreset-gpio + If present (and supported by the specific board), indicates a + GPIO that can be set to trigger a system reset. It is assumed + that such a system reset will effect a complete platform reset, + being roughly equivalent to a power-on reset.