allwinner: Scan AXP803 FDT node to setup initial power rails
Now that we have a pointer to the device tree blob, let's use that to
do some initial setup of the PMIC:
- We scan the DT for the compatible string to find the PMIC node.
- We switch the N_VBUSEN pin if the DT property tells us so.
- We scan over all regulator subnodes, and switch DC1SW if there is at
least one other node referencing it (judging by the existence of a
phandle property in that subnode).
This is just the first part of the setup, a follow up patch will setup
voltages.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/plat/allwinner/sun50i_a64/sunxi_power.c b/plat/allwinner/sun50i_a64/sunxi_power.c
index 48d01d0..0d73371 100644
--- a/plat/allwinner/sun50i_a64/sunxi_power.c
+++ b/plat/allwinner/sun50i_a64/sunxi_power.c
@@ -10,6 +10,7 @@
#include <debug.h>
#include <delay_timer.h>
#include <errno.h>
+#include <libfdt.h>
#include <mmio.h>
#include <platform_def.h>
#include <sunxi_def.h>
@@ -126,6 +127,52 @@
return rsb_write(AXP803_RT_ADDR, reg, regval);
}
+static bool should_enable_regulator(const void *fdt, int node)
+{
+ if (fdt_getprop(fdt, node, "phandle", NULL) != NULL)
+ return true;
+ if (fdt_getprop(fdt, node, "regulator-always-on", NULL) != NULL)
+ return true;
+ return false;
+}
+
+static void setup_axp803_rails(const void *fdt)
+{
+ int node;
+
+ /* locate the PMIC DT node, bail out if not found */
+ node = fdt_node_offset_by_compatible(fdt, -1, "x-powers,axp803");
+ if (node == -FDT_ERR_NOTFOUND) {
+ WARN("BL31: PMIC: No AXP803 DT node, skipping initial setup.\n");
+ return;
+ }
+
+ if (fdt_getprop(fdt, node, "x-powers,drive-vbus-en", NULL))
+ axp_setbits(0x8f, BIT(4));
+
+ /* descend into the "regulators" subnode */
+ node = fdt_first_subnode(fdt, node);
+
+ /* iterate over all regulators to find used ones */
+ for (node = fdt_first_subnode(fdt, node);
+ node != -FDT_ERR_NOTFOUND;
+ node = fdt_next_subnode(fdt, node)) {
+ const char *name;
+ int length;
+
+ /* We only care if it's always on or referenced. */
+ if (!should_enable_regulator(fdt, node))
+ continue;
+
+ name = fdt_get_name(fdt, node, &length);
+ if (!strncmp(name, "dc1sw", length)) {
+ INFO("PMIC: AXP803: Enabling DC1SW\n");
+ axp_setbits(0x12, BIT(7));
+ continue;
+ }
+ }
+}
+
int sunxi_pmic_setup(uint16_t socid, const void *fdt)
{
int ret;
@@ -148,6 +195,9 @@
pmic = AXP803_RSB;
NOTICE("BL31: PMIC: Detected AXP803 on RSB.\n");
+ if (fdt)
+ setup_axp803_rails(fdt);
+
break;
default:
NOTICE("BL31: PMIC: No support for Allwinner %x SoC.\n", socid);