Handle drive strength.

1 files changed, 67 insertions, 13 deletions

diff --git a/sys/dev/fdt/rkpinctrl.c b/sys/dev/fdt/rkpinctrl.c
index 4f9b8ee70d4..6302416b884 100644
--- a/sys/dev/fdt/rkpinctrl.c
+++ b/sys/dev/fdt/rkpinctrl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rkpinctrl.c,v 1.2 2017/05/06 18:25:43 kettenis Exp $	*/
+/*	$OpenBSD: rkpinctrl.c,v 1.3 2017/05/13 12:25:55 kettenis Exp $	*/
 /*
  * Copyright (c) 2017 Mark Kettenis <kettenis@openbsd.org>
  *
@@ -118,19 +118,56 @@ rk3399_pull(uint32_t bank, uint32_t idx, uint32_t phandle)
 	return -1;
 }
 
+/* Magic because the drive strength configurations vary wildly. */
+
+int rk3399_strength_levels[][8] = {
+	{ 2, 4, 8, 12 },			/* default */
+	{ 3, 6, 9, 12 },			/* 1.8V or 3.0V */
+	{ 5, 10, 15, 20 },			/* 1.8V only */
+	{ 4, 6, 8, 10, 12, 14, 16, 18 },	/* 1.8V or 3.0V auto */
+	{ 4, 7, 10, 13, 16, 19, 22, 26 },	/* 3.3V */
+};
+
+int rk3399_strength_types[][4] = {
+	{ 2, 2, 0, 0 },
+	{ 1, 1, 1, 1 },
+	{ 1, 1, 2, 2 },
+	{ 4, 4, 4, 1 },
+	{ 1, 3, 1, 1 },
+};
+
+int rk3399_strength_regs[][4] = {
+	{ 0x0080, 0x0088, 0x0090, 0x0098 },
+	{ 0x00a0, 0x00a8, 0x00b0, 0x00b8 },
+	{ 0x0100, 0x0104, 0x0108, 0x010c },
+	{ 0x0110, 0x0118, 0x0120, 0x0128 },
+	{ 0x012c, 0x0130, 0x0138, 0x013c },
+};
+
 int
-rk3399_strength(uint32_t phandle)
+rk3399_strength(uint32_t bank, uint32_t idx, uint32_t phandle)
 {
+	int strength, type, level;
+	int *levels;
 	int node;
 
 	node = OF_getnodebyphandle(phandle);
 	if (node == 0)
 		return -1;
 
-	/* XXX decode levels. */
-	return OF_getpropint(node, "drive-strength", -1);
-}
+	strength = OF_getpropint(node, "drive-strength", -1);
+	if (strength == -1)
+		return -1;
 
+	/* Convert drive strength to level. */
+	type = rk3399_strength_types[bank][idx / 8];
+	levels = rk3399_strength_levels[type];
+	for (level = 7; level >= 0; level--) {
+		if (strength >= levels[level] && levels[level] > 0)
+			break;
+	}
+	return level;
+}
 
 int
 rk3399_pinctrl(uint32_t phandle, void *cookie)
@@ -155,32 +192,30 @@ rk3399_pinctrl(uint32_t phandle, void *cookie)
 		struct regmap *rm;
 		bus_size_t base, off;
 		uint32_t bank, idx, mux;
-		int pull, strength;
+		int pull, strength, type, shift;
 		uint32_t mask, bits;
+		int s;
 
 		bank = pins[i];
 		idx = pins[i + 1];
 		mux = pins[i + 2];
 		pull = rk3399_pull(bank, idx, pins[i + 3]);
-		strength = rk3399_strength(pins[i + 3]);
+		strength = rk3399_strength(bank, idx, pins[i + 3]);
 
 		if (bank > 5 || idx > 32 || mux > 3)
 			continue;
 
-		/* XXX leave alone for now */
-		if (strength >= 0)
-			continue;
-
 		/* Bank 0 and 1 live in the PMU. */
 		if (bank < 2) {
 			rm = sc->sc_pmu;
 			base = RK3399_PMUGRF_GPIO0A_IOMUX;
 		} else {
 			rm = sc->sc_grf;
-			base = RK3399_GRF_GPIO2A_IOMUX;
-			bank -= 2;
+			base = RK3399_GRF_GPIO2A_IOMUX - 0x20;
 		}
 
+		s = splhigh();
+
 		/* IOMUX control */
 		off = bank * 0x10 + (idx / 8) * 0x04;
 		mask = (0x3 << ((idx % 8) * 2));
@@ -194,6 +229,25 @@ rk3399_pinctrl(uint32_t phandle, void *cookie)
 			bits = (pull << ((idx % 8) * 2));
 			regmap_write_4(rm, base + off, mask << 16 | bits);
 		}
+
+		/* GPIO drive strength control */
+		if (strength >= 0) {
+			off = rk3399_strength_regs[bank][idx / 8];
+			type = rk3399_strength_types[bank][idx / 8];
+			shift = (type > 2) ? 3 : 2;
+			mask = (((1 << shift) - 1) << ((idx % 8) * shift));
+			bits = (strength << ((idx % 8) * shift));
+			if (mask & 0x0000ffff) {
+				regmap_write_4(rm, base + off,
+				    mask << 16 | (bits & 0x0000ffff));
+			}
+			if (mask & 0xffff0000) {
+				regmap_write_4(rm, base + off + 0x04,
+				    (mask & 0xffff0000) | bits >> 16);
+			}
+		}
+
+		splx(s);
 	}
 
 	free(pins, M_TEMP, len);