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Commit f3fbaf34 authored by Ben Skeggs's avatar Ben Skeggs
Browse files

drm/nv50/pm: rewrite clock management, and switch to the new pm hooks



This area is horrifically complicated on these chipsets, and it's likely we
will need at least a few more tweaks yet.

Oh yes, and it's completely disabled on IGPs for the moment.  From traces,
things look potentially different there yet again.  Sigh...

Signed-off-by: default avatarBen Skeggs <bskeggs@redhat.com>
parent d4cca9e1
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+1 −0
Original line number Diff line number Diff line
@@ -493,6 +493,7 @@ struct nouveau_pm_level {
	u32 copy;
	u32 daemon;
	u32 vdec;
	u32 dom6;
	u32 unka0;	/* nva3:nvc0 */
	u32 hub01;	/* nvc0- */
	u32 hub06;	/* nvc0- */
+1 −0
Original line number Diff line number Diff line
@@ -302,6 +302,7 @@ nouveau_perf_init(struct drm_device *dev)
			perflvl->shader = ROM16(entry[10]) * 1000;
			perflvl->memory = ROM16(entry[12]) * 1000;
			perflvl->vdec = ROM16(entry[16]) * 1000;
			perflvl->dom6 = ROM16(entry[20]) * 1000;
			break;
		case 0x40:
#define subent(n) (ROM16(entry[perf[2] + ((n) * perf[3])]) & 0xfff) * 1000
+3 −4
Original line number Diff line number Diff line
@@ -60,10 +60,9 @@ int nv40_pm_pwm_get(struct drm_device *, struct dcb_gpio_entry *, u32*, u32*);
int nv40_pm_pwm_set(struct drm_device *, struct dcb_gpio_entry *, u32, u32);

/* nv50_pm.c */
int nv50_pm_clock_get(struct drm_device *, u32 id);
void *nv50_pm_clock_pre(struct drm_device *, struct nouveau_pm_level *,
			u32 id, int khz);
void nv50_pm_clock_set(struct drm_device *, void *);
int nv50_pm_clocks_get(struct drm_device *, struct nouveau_pm_level *);
void *nv50_pm_clocks_pre(struct drm_device *, struct nouveau_pm_level *);
int nv50_pm_clocks_set(struct drm_device *, void *);
int nv50_pm_pwm_get(struct drm_device *, struct dcb_gpio_entry *, u32*, u32*);
int nv50_pm_pwm_set(struct drm_device *, struct dcb_gpio_entry *, u32, u32);

+3 −3
Original line number Diff line number Diff line
@@ -356,9 +356,9 @@ static int nouveau_init_engine_ptrs(struct drm_device *dev)
		case 0xaa:
		case 0xac:
		case 0x50:
			engine->pm.clock_get	= nv50_pm_clock_get;
			engine->pm.clock_pre	= nv50_pm_clock_pre;
			engine->pm.clock_set	= nv50_pm_clock_set;
			engine->pm.clocks_get	= nv50_pm_clocks_get;
			engine->pm.clocks_pre	= nv50_pm_clocks_pre;
			engine->pm.clocks_set	= nv50_pm_clocks_set;
			break;
		default:
			engine->pm.clocks_get	= nva3_pm_clocks_get;
+568 −90
Original line number Diff line number Diff line
@@ -25,123 +25,601 @@
#include "drmP.h"
#include "nouveau_drv.h"
#include "nouveau_bios.h"
#include "nouveau_hw.h"
#include "nouveau_pm.h"

struct nv50_pm_state {
	struct nouveau_pm_level *perflvl;
	struct pll_lims pll;
	enum pll_types type;
	int N, M, P;
enum clk_src {
	clk_src_crystal,
	clk_src_href,
	clk_src_hclk,
	clk_src_hclkm3,
	clk_src_hclkm3d2,
	clk_src_host,
	clk_src_nvclk,
	clk_src_sclk,
	clk_src_mclk,
	clk_src_vdec,
	clk_src_dom6
};

static u32 read_clk(struct drm_device *, enum clk_src);

static u32
read_div(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;

	switch (dev_priv->chipset) {
	case 0x50: /* it exists, but only has bit 31, not the dividers.. */
	case 0x84:
	case 0x86:
	case 0x98:
	case 0xa0:
		return nv_rd32(dev, 0x004700);
	case 0x92:
	case 0x94:
	case 0x96:
		return nv_rd32(dev, 0x004800);
	default:
		return 0x00000000;
	}
}

static u32
read_pll_ref(struct drm_device *dev, u32 base)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	u32 coef, ref = read_clk(dev, clk_src_crystal);
	u32 rsel = nv_rd32(dev, 0x00e18c);
	int P, N, M, id;

	switch (dev_priv->chipset) {
	case 0x50:
	case 0xa0:
		switch (base) {
		case 0x4020:
		case 0x4028: id = !!(rsel & 0x00000004); break;
		case 0x4008: id = !!(rsel & 0x00000008); break;
		case 0x4030: id = 0; break;
		default:
			NV_ERROR(dev, "ref: bad pll 0x%06x\n", base);
			return 0;
		}

		coef = nv_rd32(dev, 0x00e81c + (id * 0x0c));
		ref *=  (coef & 0x01000000) ? 2 : 4;
		P    =  (coef & 0x00070000) >> 16;
		N    = ((coef & 0x0000ff00) >> 8) + 1;
		M    = ((coef & 0x000000ff) >> 0) + 1;
		break;
	case 0x84:
	case 0x86:
	case 0x92:
		coef = nv_rd32(dev, 0x00e81c);
		P    = (coef & 0x00070000) >> 16;
		N    = (coef & 0x0000ff00) >> 8;
		M    = (coef & 0x000000ff) >> 0;
		break;
	case 0x94:
	case 0x96:
	case 0x98:
		rsel = nv_rd32(dev, 0x00c050);
		switch (base) {
		case 0x4020: rsel = (rsel & 0x00000003) >> 0; break;
		case 0x4008: rsel = (rsel & 0x0000000c) >> 2; break;
		case 0x4028: rsel = (rsel & 0x00001800) >> 11; break;
		case 0x4030: rsel = 3; break;
		default:
			NV_ERROR(dev, "ref: bad pll 0x%06x\n", base);
			return 0;
		}

		switch (rsel) {
		case 0: id = 1; break;
		case 1: return read_clk(dev, clk_src_crystal);
		case 2: return read_clk(dev, clk_src_href);
		case 3: id = 0; break;
		}

		coef =  nv_rd32(dev, 0x00e81c + (id * 0x28));
		P    = (nv_rd32(dev, 0x00e824 + (id * 0x28)) >> 16) & 7;
		P   += (coef & 0x00070000) >> 16;
		N    = (coef & 0x0000ff00) >> 8;
		M    = (coef & 0x000000ff) >> 0;
		break;
	default:
		BUG_ON(1);
	}

	if (M)
		return (ref * N / M) >> P;
	return 0;
}

static u32
read_pll(struct drm_device *dev, u32 base)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	u32 mast = nv_rd32(dev, 0x00c040);
	u32 src = 0, ref = 0, clk = 0;
	u32 ctrl, coef;
	int N1, N2, M1, M2;

	switch (base) {
	case 0x004028:
		if (mast & 0x00100000) {
			/* wtf, appears to only disable post-divider on nva0 */
			if (dev_priv->chipset != 0xa0)
				return read_clk(dev, clk_src_dom6);
		}
		src = !!(mast & 0x00200000);
		break;
	case 0x004020:
		src = !!(mast & 0x00400000);
		break;
	case 0x004008:
		src = !!(mast & 0x00010000);
		break;
	case 0x004030:
		src = !!(mast & 0x02000000);
		break;
	case 0x00e810:
		ref = read_clk(dev, clk_src_crystal);
		break;
	default:
		NV_ERROR(dev, "bad pll 0x%06x\n", base);
		return 0;
	}

	if (ref == 0) {
		if (src)
			ref = read_clk(dev, clk_src_href);
		else
			ref = read_pll_ref(dev, base);
	}

	ctrl = nv_rd32(dev, base + 0);
	coef = nv_rd32(dev, base + 4);

	N2 = (coef & 0xff000000) >> 24;
	M2 = (coef & 0x00ff0000) >> 16;
	N1 = (coef & 0x0000ff00) >> 8;
	M1 = (coef & 0x000000ff);
	if ((ctrl & 0x80000000) && M1) {
		clk = ref * N1 / M1;
		if ((ctrl & 0x40000100) == 0x40000000) {
			if (M2)
				clk = clk * N2 / M2;
			else
				clk = 0;
		}
	}

	return clk;
}

static u32
read_clk(struct drm_device *dev, enum clk_src src)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	u32 mast = nv_rd32(dev, 0x00c040);
	u32 P = 0;

	switch (src) {
	case clk_src_crystal:
		return dev_priv->crystal;
	case clk_src_href:
		return 100000; /* PCIE reference clock */
	case clk_src_hclk:
		return read_clk(dev, clk_src_href) * 27778 / 10000;
	case clk_src_hclkm3:
		return read_clk(dev, clk_src_hclk) * 3;
	case clk_src_hclkm3d2:
		return read_clk(dev, clk_src_hclk) * 3 / 2;
	case clk_src_host:
		switch (mast & 0x30000000) {
		case 0x00000000: return read_clk(dev, clk_src_href);
		case 0x10000000: break;
		case 0x20000000: /* !0x50 */
		case 0x30000000: return read_clk(dev, clk_src_hclk);
		}
		break;
	case clk_src_nvclk:
		if (!(mast & 0x00100000))
			P = (nv_rd32(dev, 0x004028) & 0x00070000) >> 16;
		switch (mast & 0x00000003) {
		case 0x00000000: return read_clk(dev, clk_src_crystal) >> P;
		case 0x00000001: return read_clk(dev, clk_src_dom6);
		case 0x00000002: return read_pll(dev, 0x004020) >> P;
		case 0x00000003: return read_pll(dev, 0x004028) >> P;
		}
		break;
	case clk_src_sclk:
		P = (nv_rd32(dev, 0x004020) & 0x00070000) >> 16;
		switch (mast & 0x00000030) {
		case 0x00000000:
			if (mast & 0x00000080)
				return read_clk(dev, clk_src_host) >> P;
			return read_clk(dev, clk_src_crystal) >> P;
		case 0x00000010: break;
		case 0x00000020: return read_pll(dev, 0x004028) >> P;
		case 0x00000030: return read_pll(dev, 0x004020) >> P;
		}
		break;
	case clk_src_mclk:
		P = (nv_rd32(dev, 0x004008) & 0x00070000) >> 16;
		if (nv_rd32(dev, 0x004008) & 0x00000200) {
			switch (mast & 0x0000c000) {
			case 0x00000000:
				return read_clk(dev, clk_src_crystal) >> P;
			case 0x00008000:
			case 0x0000c000:
				return read_clk(dev, clk_src_href) >> P;
			}
		} else {
			return read_pll(dev, 0x004008) >> P;
		}
		break;
	case clk_src_vdec:
		P = (read_div(dev) & 0x00000700) >> 8;
		switch (dev_priv->chipset) {
		case 0x84:
		case 0x86:
		case 0x92:
		case 0x94:
		case 0x96:
		case 0xa0:
			switch (mast & 0x00000c00) {
			case 0x00000000:
				if (dev_priv->chipset == 0xa0) /* wtf?? */
					return read_clk(dev, clk_src_nvclk) >> P;
				return read_clk(dev, clk_src_crystal) >> P;
			case 0x00000400:
				return 0;
			case 0x00000800:
				if (mast & 0x01000000)
					return read_pll(dev, 0x004028) >> P;
				return read_pll(dev, 0x004030) >> P;
			case 0x00000c00:
				return read_clk(dev, clk_src_nvclk) >> P;
			}
			break;
		case 0x98:
			switch (mast & 0x00000c00) {
			case 0x00000000:
				return read_clk(dev, clk_src_nvclk) >> P;
			case 0x00000400:
				return 0;
			case 0x00000800:
				return read_clk(dev, clk_src_hclkm3d2) >> P;
			case 0x00000c00:
				return read_pll(dev, clk_src_mclk) >> P;
			}
			break;
		}
		break;
	case clk_src_dom6:
		switch (dev_priv->chipset) {
		case 0x50:
		case 0xa0:
			return read_pll(dev, 0x00e810) >> 2;
		case 0x84:
		case 0x86:
		case 0x92:
		case 0x94:
		case 0x96:
		case 0x98:
			P = (read_div(dev) & 0x00000007) >> 0;
			switch (mast & 0x0c000000) {
			case 0x00000000: return read_clk(dev, clk_src_href);
			case 0x04000000: break;
			case 0x08000000: return read_clk(dev, clk_src_hclk);
			case 0x0c000000:
				return read_clk(dev, clk_src_hclkm3) >> P;
			}
			break;
		default:
			break;
		}
	default:
		break;
	}

	NV_DEBUG(dev, "unknown clock source %d 0x%08x\n", src, mast);
	return 0;
}

int
nv50_pm_clock_get(struct drm_device *dev, u32 id)
nv50_pm_clocks_get(struct drm_device *dev, struct nouveau_pm_level *perflvl)
{
	struct pll_lims pll;
	int P, N, M, ret;
	u32 reg0, reg1;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	if (dev_priv->chipset == 0xaa ||
	    dev_priv->chipset == 0xac)
		return 0;

	ret = get_pll_limits(dev, id, &pll);
	perflvl->core   = read_clk(dev, clk_src_nvclk);
	perflvl->shader = read_clk(dev, clk_src_sclk);
	perflvl->memory = read_clk(dev, clk_src_mclk);
	if (dev_priv->chipset != 0x50) {
		perflvl->vdec = read_clk(dev, clk_src_vdec);
		perflvl->dom6 = read_clk(dev, clk_src_dom6);
	}

	return 0;
}

struct nv50_pm_state {
	u32 emast;
	u32 nctrl;
	u32 ncoef;
	u32 sctrl;
	u32 scoef;

	u32 amast;
	u32 pdivs;

	u32 mscript;
	u32 mctrl;
	u32 mcoef;
};

static u32
calc_pll(struct drm_device *dev, u32 reg, struct pll_lims *pll,
	 u32 clk, int *N1, int *M1, int *log2P)
{
	struct nouveau_pll_vals coef;
	int ret;

	ret = get_pll_limits(dev, reg, pll);
	if (ret)
		return ret;
		return 0;

	pll->vco2.maxfreq = 0;
	pll->refclk = read_pll_ref(dev, reg);
	if (!pll->refclk)
		return 0;

	reg0 = nv_rd32(dev, pll.reg + 0);
	reg1 = nv_rd32(dev, pll.reg + 4);
	ret = nouveau_calc_pll_mnp(dev, pll, clk, &coef);
	if (ret == 0)
		return 0;

	if ((reg0 & 0x80000000) == 0) {
		if (id == PLL_SHADER) {
			NV_DEBUG(dev, "Shader PLL is disabled. "
				"Shader clock is twice the core\n");
			ret = nv50_pm_clock_get(dev, PLL_CORE);
			if (ret > 0)
				return ret << 1;
		} else if (id == PLL_MEMORY) {
			NV_DEBUG(dev, "Memory PLL is disabled. "
				"Memory clock is equal to the ref_clk\n");
			return pll.refclk;
	*N1 = coef.N1;
	*M1 = coef.M1;
	*log2P = coef.log2P;
	return ret;
}

static inline u32
calc_div(u32 src, u32 target, int *div)
{
	u32 clk0 = src, clk1 = src;
	for (*div = 0; *div <= 7; (*div)++) {
		if (clk0 <= target) {
			clk1 = clk0 << (*div ? 1 : 0);
			break;
		}
		clk0 >>= 1;
	}

	P = (reg0 & 0x00070000) >> 16;
	N = (reg1 & 0x0000ff00) >> 8;
	M = (reg1 & 0x000000ff);
	if (target - clk0 <= clk1 - target)
		return clk0;
	(*div)--;
	return clk1;
}

	return ((pll.refclk * N / M) >> P);
static inline u32
clk_same(u32 a, u32 b)
{
	return ((a / 1000) == (b / 1000));
}

void *
nv50_pm_clock_pre(struct drm_device *dev, struct nouveau_pm_level *perflvl,
		  u32 id, int khz)
nv50_pm_clocks_pre(struct drm_device *dev, struct nouveau_pm_level *perflvl)
{
	struct nv50_pm_state *state;
	int dummy, ret;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nv50_pm_state *info;
	struct pll_lims pll;
	int ret = -EINVAL;
	int N, M, P1, P2;
	u32 clk, out;

	if (dev_priv->chipset == 0xaa ||
	    dev_priv->chipset == 0xac)
		return ERR_PTR(-ENODEV);

	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (!state)
	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		return ERR_PTR(-ENOMEM);
	state->type = id;
	state->perflvl = perflvl;

	ret = get_pll_limits(dev, id, &state->pll);
	if (ret < 0) {
		kfree(state);
		return (ret == -ENOENT) ? NULL : ERR_PTR(ret);
	/* core: for the moment at least, always use nvpll */
	clk = calc_pll(dev, 0x4028, &pll, perflvl->core, &N, &M, &P1);
	if (clk == 0)
		goto error;

	info->emast = 0x00000003;
	info->nctrl = 0x80000000 | (P1 << 19) | (P1 << 16);
	info->ncoef = (N << 8) | M;

	/* shader: tie to nvclk if possible, otherwise use spll.  have to be
	 * very careful that the shader clock is at least twice the core, or
	 * some chipsets will be very unhappy.  i expect most or all of these
	 * cases will be handled by tying to nvclk, but it's possible there's
	 * corners
	 */
	if (P1-- && perflvl->shader == (perflvl->core << 1)) {
		info->emast |= 0x00000020;
		info->sctrl  = 0x00000000 | (P1 << 19) | (P1 << 16);
		info->scoef  = nv_rd32(dev, 0x004024);
	} else {
		clk = calc_pll(dev, 0x4020, &pll, perflvl->shader, &N, &M, &P1);
		if (clk == 0)
			goto error;

		info->emast |= 0x00000030;
		info->sctrl  = 0x80000000 | (P1 << 19) | (P1 << 16);
		info->scoef  = (N << 8) | M;
	}

	ret = nv50_calc_pll(dev, &state->pll, khz, &state->N, &state->M,
			    &dummy, &dummy, &state->P);
	if (ret < 0) {
		kfree(state);
		return ERR_PTR(ret);
	/* memory: use pcie refclock if possible, otherwise use mpll */
	info->mscript = perflvl->memscript;
	if (clk_same(perflvl->memory, read_clk(dev, clk_src_href))) {
		info->mctrl = nv_rd32(dev, 0x4008) | 0x00000200;
		info->mcoef = nv_rd32(dev, 0x400c);
	} else
	if (perflvl->memory) {
		clk = calc_pll(dev, 0x4008, &pll, perflvl->memory,
			       &N, &M, &P1);
		if (clk == 0)
			goto error;

		info->mctrl  = 0x80000000 | (P1 << 22) | (P1 << 16);
		info->mctrl |= pll.log2p_bias << 19;
		info->mcoef  = (N << 8) | M;
	} else {
		info->mctrl = 0x00000000;
	}

	return state;
	/* vdec: avoid modifying xpll until we know exactly how the other
	 * clock domains work, i suspect at least some of them can also be
	 * tied to xpll...
	 */
	info->amast = info->pdivs = 0;
	if (perflvl->vdec) {
		/* see how close we can get using nvclk as a source */
		clk = calc_div(perflvl->core, perflvl->vdec, &P1);

		/* see how close we can get using xpll/hclk as a source */
		if (dev_priv->chipset != 0x98)
			out = read_pll(dev, 0x004030);
		else
			out = read_clk(dev, clk_src_hclkm3d2);
		out = calc_div(out, perflvl->vdec, &P2);

		/* select whichever gets us closest */
		if (abs((int)perflvl->vdec - clk) <=
		    abs((int)perflvl->vdec - out)) {
			if (dev_priv->chipset != 0x98)
				info->amast |= 0x00000c00;
			else
				info->amast |= 0x00000000;
			info->pdivs |= P1 << 8;
		} else {
			info->amast |= 0x00000800;
			info->pdivs |= P2 << 8;
		}
	}

	/* dom6: nfi what this is, but we're limited to various combinations
	 * of the host clock frequency
	 */
	if (clk_same(perflvl->dom6, read_clk(dev, clk_src_href))) {
		info->amast |= 0x00000000;
		info->pdivs |= read_div(dev) & 0x00000007;
	} else
	if (clk_same(perflvl->dom6, read_clk(dev, clk_src_hclk))) {
		info->amast |= 0x08000000;
		info->pdivs |= read_div(dev) & 0x00000007;
	} else
	if (perflvl->dom6) {
		clk = read_clk(dev, clk_src_hclk) * 3;
		clk = calc_div(clk, perflvl->dom6, &P1);

		info->amast |= 0x0c000000;
		info->pdivs |= P1;
	}


	return info;
error:
	kfree(info);
	return ERR_PTR(ret);
}

void
nv50_pm_clock_set(struct drm_device *dev, void *pre_state)
int
nv50_pm_clocks_set(struct drm_device *dev, void *data)
{
	struct nv50_pm_state *state = pre_state;
	struct nouveau_pm_level *perflvl = state->perflvl;
	u32 reg = state->pll.reg, tmp;
	struct bit_entry BIT_M;
	u16 script;
	int N = state->N;
	int M = state->M;
	int P = state->P;

	if (state->type == PLL_MEMORY && perflvl->memscript &&
	    bit_table(dev, 'M', &BIT_M) == 0 &&
	    BIT_M.version == 1 && BIT_M.length >= 0x0b) {
		script = ROM16(BIT_M.data[0x05]);
		if (script)
			nouveau_bios_run_init_table(dev, script, NULL, -1);
		script = ROM16(BIT_M.data[0x07]);
		if (script)
			nouveau_bios_run_init_table(dev, script, NULL, -1);
		script = ROM16(BIT_M.data[0x09]);
		if (script)
			nouveau_bios_run_init_table(dev, script, NULL, -1);

		nouveau_bios_run_init_table(dev, perflvl->memscript, NULL, -1);
	}

	if (state->type == PLL_MEMORY) {
		nv_wr32(dev, 0x100210, 0);
		nv_wr32(dev, 0x1002dc, 1);
	}

	tmp  = nv_rd32(dev, reg + 0) & 0xfff8ffff;
	tmp |= 0x80000000 | (P << 16);
	nv_wr32(dev, reg + 0, tmp);
	nv_wr32(dev, reg + 4, (N << 8) | M);

	if (state->type == PLL_MEMORY) {
		nv_wr32(dev, 0x1002dc, 0);
		nv_wr32(dev, 0x100210, 0x80000000);
	}

	kfree(state);
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nv50_pm_state *info = data;
	struct bit_entry M;
	int ret = 0;

	/* halt and idle execution engines */
	nv_mask(dev, 0x002504, 0x00000001, 0x00000001);
	if (!nv_wait(dev, 0x002504, 0x00000010, 0x00000010))
		goto error;

	/* reclock vdec/dom6 */
	nv_mask(dev, 0x00c040, 0x00000c00, 0x00000000);
	switch (dev_priv->chipset) {
	case 0x92:
	case 0x94:
	case 0x96:
		nv_mask(dev, 0x004800, 0x00000707, info->pdivs);
		break;
	default:
		nv_mask(dev, 0x004700, 0x00000707, info->pdivs);
		break;
	}
	nv_mask(dev, 0x00c040, 0x0c000c00, info->amast);

	/* core/shader: switch core to dom6, shader to hclk */
	if (dev_priv->chipset == 0x50)
		nv_mask(dev, 0x00c040, 0x001000b0, 0x00100080); /* grrr! */
	else
		nv_mask(dev, 0x00c040, 0x000000b3, 0x00000081);
	nv_mask(dev, 0x004020, 0xc03f0100, info->sctrl);
	nv_wr32(dev, 0x004024, info->scoef);
	nv_mask(dev, 0x004028, 0xc03f0100, info->nctrl);
	nv_wr32(dev, 0x00402c, info->ncoef);
	nv_mask(dev, 0x00c040, 0x00100033, info->emast);

	/* memory */
	if (!info->mctrl)
		goto resume;

	/* execute some scripts that do ??? from the vbios.. */
	if (!bit_table(dev, 'M', &M) && M.version == 1) {
		if (M.length >= 6)
			nouveau_bios_init_exec(dev, ROM16(M.data[5]));
		if (M.length >= 8)
			nouveau_bios_init_exec(dev, ROM16(M.data[7]));
		if (M.length >= 10)
			nouveau_bios_init_exec(dev, ROM16(M.data[9]));
		nouveau_bios_init_exec(dev, info->mscript);
	}

	/* disable display */
	nv_wr32(dev, 0x611200, 0x00003300);
	udelay(100);

	/* prepare ram for reclocking */
	nv_wr32(dev, 0x1002d4, 0x00000001); /* precharge */
	nv_wr32(dev, 0x1002d0, 0x00000001); /* refresh */
	nv_wr32(dev, 0x1002d0, 0x00000001); /* refresh */
	nv_mask(dev, 0x100210, 0x80000000, 0x00000000); /* no auto-refresh */
	nv_wr32(dev, 0x1002dc, 0x00000001); /* enable self-refresh */

	/* modify mpll */
	nv_mask(dev, 0x00c040, 0x0000c000, 0x0000c000);
	nv_mask(dev, 0x004008, 0x81ff0200, 0x00000200 | info->mctrl);
	nv_wr32(dev, 0x00400c, info->mcoef);
	udelay(100);
	nv_mask(dev, 0x004008, 0x81ff0200, info->mctrl);

	/* re-enable normal operation of memory controller */
	nv_wr32(dev, 0x1002dc, 0x00000000);
	nv_mask(dev, 0x100210, 0x80000000, 0x80000000);
	udelay(100);

	/* re-enable display */
	nv_wr32(dev, 0x611200, 0x00003330);

	goto resume;
error:
	ret = -EBUSY;
resume:
	nv_mask(dev, 0x002504, 0x00000001, 0x00000000);
	return ret;
}

static int