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 <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
diff --git a/board/synopsys/hsdk/hsdk.c b/board/synopsys/hsdk/hsdk.c
index 329427e..a3e0563 100644
--- a/board/synopsys/hsdk/hsdk.c
+++ b/board/synopsys/hsdk/hsdk.c
@@ -42,6 +42,8 @@
#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 @@
"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 @@
}
/* 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;
}