drm/nvc0/pm: initial implementation of clocks_get()

Not too certain on memory clock yet, but it gets the right numbers for
each perflvl on my NVC0.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/Makefile

@@ -30,7 +30,7 @@ nouveau-y := nouveau_drv.o nouveau_state.o nouveau_channel.o nouveau_mem.o \
              nv04_fbcon.o nv50_fbcon.o nvc0_fbcon.o \
              nv10_gpio.o nv50_gpio.o \
 	     nv50_calc.o \
-	     nv04_pm.o nv50_pm.o nva3_pm.o \
+	     nv04_pm.o nv50_pm.o nva3_pm.o nvc0_pm.o \
 	     nv50_vram.o nvc0_vram.o \
 	     nv50_vm.o nvc0_vm.o
 

drivers/gpu/drm/nouveau/nouveau_pm.h

@@ -63,6 +63,9 @@ int nva3_pm_clocks_get(struct drm_device *, struct nouveau_pm_level *);
 void *nva3_pm_clocks_pre(struct drm_device *, struct nouveau_pm_level *);
 void nva3_pm_clocks_set(struct drm_device *, void *);
 
+/* nvc0_pm.c */
+int nvc0_pm_clocks_get(struct drm_device *, struct nouveau_pm_level *);
+
 /* nouveau_temp.c */
 void nouveau_temp_init(struct drm_device *dev);
 void nouveau_temp_fini(struct drm_device *dev);

drivers/gpu/drm/nouveau/nouveau_state.c

@@ -422,6 +422,7 @@ static int nouveau_init_engine_ptrs(struct drm_device *dev)
 		engine->vram.put		= nv50_vram_del;
 		engine->vram.flags_valid	= nvc0_vram_flags_valid;
 		engine->pm.temp_get		= nv84_temp_get;
+		engine->pm.clocks_get		= nvc0_pm_clocks_get;
 		engine->pm.voltage_get		= nouveau_voltage_gpio_get;
 		engine->pm.voltage_set		= nouveau_voltage_gpio_set;
 		break;

drivers/gpu/drm/nouveau/nvc0_pm.c

+/*
+ * Copyright 2011 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Ben Skeggs
+ */
+
+#include "drmP.h"
+#include "nouveau_drv.h"
+#include "nouveau_bios.h"
+#include "nouveau_pm.h"
+
+static u32 read_div(struct drm_device *, int, u32, u32);
+static u32 read_pll(struct drm_device *, u32);
+
+static u32
+read_vco(struct drm_device *dev, u32 dsrc)
+{
+	u32 ssrc = nv_rd32(dev, dsrc);
+	if (!(ssrc & 0x00000100))
+		return read_pll(dev, 0x00e800);
+	return read_pll(dev, 0x00e820);
+}
+
+static u32
+read_pll(struct drm_device *dev, u32 pll)
+{
+	u32 coef = nv_rd32(dev, pll + 4);
+	u32 P = (coef & 0x003f0000) >> 16;
+	u32 N = (coef & 0x0000ff00) >> 8;
+	u32 M = (coef & 0x000000ff) >> 0;
+	u32 sclk, doff;
+
+	switch (pll & 0xfff000) {
+	case 0x00e000:
+		sclk = 27000;
+		P = 1;
+		break;
+	case 0x137000:
+		doff = (pll - 0x137000) / 0x20;
+		sclk = read_div(dev, doff, 0x137120, 0x137140);
+		break;
+	case 0x132000:
+		switch (pll) {
+		case 0x132000:
+			sclk = read_pll(dev, 0x132020);
+			break;
+		case 0x132020:
+			sclk = read_div(dev, 0, 0x137320, 0x137330);
+			break;
+		default:
+			return 0;
+		}
+		break;
+	default:
+		return 0;
+	}
+
+	return sclk * N / M / P;
+}
+
+static u32
+read_div(struct drm_device *dev, int doff, u32 dsrc, u32 dctl)
+{
+	u32 ssrc = nv_rd32(dev, dsrc + (doff * 4));
+	u32 sctl = nv_rd32(dev, dctl + (doff * 4));
+
+	switch (ssrc & 0x00000003) {
+	case 0:
+		if ((ssrc & 0x00030000) != 0x00030000)
+			return 27000;
+		return 108000;
+	case 2:
+		return 100000;
+	case 3:
+		if (sctl & 0x80000000) {
+			u32 sclk = read_vco(dev, dsrc);
+			u32 sdiv = (sctl & 0x0000003f) + 2;
+			return (sclk * 2) / sdiv;
+		}
+
+		return read_vco(dev, dsrc);
+	default:
+		return 0;
+	}
+}
+
+static u32
+read_mem(struct drm_device *dev)
+{
+	u32 ssel = nv_rd32(dev, 0x1373f0);
+	if (ssel & 0x00000001)
+		return read_div(dev, 0, 0x137300, 0x137310);
+	return read_pll(dev, 0x132000);
+}
+
+static u32
+read_clk(struct drm_device *dev, int clk)
+{
+	u32 sctl = nv_rd32(dev, 0x137250 + (clk * 4));
+	u32 ssel = nv_rd32(dev, 0x137100);
+	u32 sclk, sdiv;
+
+	if (ssel & (1 << clk)) {
+		if (clk < 7)
+			sclk = read_pll(dev, 0x137000 + (clk * 0x20));
+		else
+			sclk = read_pll(dev, 0x1370e0);
+		sdiv = ((sctl & 0x00003f00) >> 8) + 2;
+	} else {
+		sclk = read_div(dev, clk, 0x137160, 0x1371d0);
+		sdiv = ((sctl & 0x0000003f) >> 0) + 2;
+	}
+
+	if (sctl & 0x80000000)
+		return (sclk * 2) / sdiv;
+	return sclk;
+}
+
+int
+nvc0_pm_clocks_get(struct drm_device *dev, struct nouveau_pm_level *perflvl)
+{
+	perflvl->shader = read_clk(dev, 0x00);
+	perflvl->core   = perflvl->shader / 2;
+	perflvl->memory = read_mem(dev);
+	perflvl->vdec   = read_clk(dev, 0x0e);
+	return 0;
+}