From 25998aed4de975262b9839bbb7ebf83e54786d20 Mon Sep 17 00:00:00 2001 From: Eugeniy Paltsev Date: Fri, 24 Apr 2020 23:11:10 +0300 Subject: [PATCH] ARC: HSDK-4xD: make init status resistant to U-boot reloading Use register intstead of static variable to store HSDK init status as we want to avoid the situation when we reload U-boot via MDB after previous init is done but HW reset (board reset) isn't done. So let's store the init status in unused register - CREG_CPU_0_ENTRY so status will survive after U-boot is reloaded via MDB. Signed-off-by: Eugeniy Paltsev Signed-off-by: Alexey Brodkin --- board/synopsys/hsdk/hsdk.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) diff --git a/board/synopsys/hsdk/hsdk.c b/board/synopsys/hsdk/hsdk.c index 329427ed4b..a3e0563ff4 100644 --- a/board/synopsys/hsdk/hsdk.c +++ b/board/synopsys/hsdk/hsdk.c @@ -42,6 +42,8 @@ DECLARE_GLOBAL_DATA_PTR; #define CREG_CPU_START_MASK 0xF #define CREG_CPU_START_POL BIT(4) +#define CREG_CPU_0_ENTRY (CREG_BASE + 0x404) + #define SDIO_BASE (ARC_PERIPHERAL_BASE + 0xA000) #define SDIO_UHS_REG_EXT (SDIO_BASE + 0x108) #define SDIO_UHS_REG_EXT_DIV_2 (2 << 30) @@ -969,9 +971,29 @@ U_BOOT_CMD( "hsdk_go halt - Boot stand-alone application on HSDK, halt CPU just before application run\n" ); +/* + * We may simply use static variable here to store init status, but we also want + * to avoid the situation when we reload U-boot via MDB after previous + * init is done but HW reset (board reset) isn't done. So let's store the + * init status in any unused register (i.e CREG_CPU_0_ENTRY) so status will + * survive after U-boot is reloaded via MDB. + */ +#define INIT_MARKER_REGISTER ((void __iomem *)CREG_CPU_0_ENTRY) +/* must be equal to INIT_MARKER_REGISTER reset value */ +#define INIT_MARKER_PENDING 0 + +static bool init_marker_get(void) +{ + return readl(INIT_MARKER_REGISTER) != INIT_MARKER_PENDING; +} + +static void init_mark_done(void) +{ + writel(~INIT_MARKER_PENDING, INIT_MARKER_REGISTER); +} + static int do_hsdk_init(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]) { - static bool done = false; int ret; if (board_mismatch()) { @@ -980,14 +1002,14 @@ static int do_hsdk_init(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[] } /* hsdk_init can be run only once */ - if (done) { + if (init_marker_get()) { printf("HSDK HW is already initialized! Please reset the board if you want to change the configuration.\n"); return CMD_RET_FAILURE; } ret = prepare_cpus(); if (!ret) - done = true; + init_mark_done(); return ret ? CMD_RET_FAILURE : CMD_RET_SUCCESS; } -- 2.39.5