drivers/gpu/drm/nouveau/nvkm/subdev/clk/gt215.c - linux - Git at Google

 /*
  * Copyright 2012 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
  *          Roy Spliet
  */
 #define gt215_clk(p) container_of((p), struct gt215_clk, base)
 #include "gt215.h"
 #include "pll.h"

 #include <engine/fifo.h>
 #include <subdev/bios.h>
 #include <subdev/bios/pll.h>
 #include <subdev/timer.h>

 struct gt215_clk {
 	struct nvkm_clk base;
 	struct gt215_clk_info eng[nv_clk_src_max];
 };

 static u32 read_clk(struct gt215_clk *, int, bool);
 static u32 read_pll(struct gt215_clk *, int, u32);

 static u32
 read_vco(struct gt215_clk *clk, int idx)
 {
 	struct nvkm_device *device = clk->base.subdev.device;
 	u32 sctl = nvkm_rd32(device, 0x4120 + (idx * 4));

 	switch (sctl & 0x00000030) {
 	case 0x00000000:
 		return device->crystal;
 	case 0x00000020:
 		return read_pll(clk, 0x41, 0x00e820);
 	case 0x00000030:
 		return read_pll(clk, 0x42, 0x00e8a0);
 	default:
 		return 0;
 	}
 }

 static u32
 read_clk(struct gt215_clk *clk, int idx, bool ignore_en)
 {
 	struct nvkm_device *device = clk->base.subdev.device;
 	u32 sctl, sdiv, sclk;

 	/* refclk for the 0xe8xx plls is a fixed frequency */
 	if (idx >= 0x40) {
 		if (device->chipset == 0xaf) {
 			/* no joke.. seriously.. sigh.. */
 			return nvkm_rd32(device, 0x00471c) * 1000;
 		}

 		return device->crystal;
 	}

 	sctl = nvkm_rd32(device, 0x4120 + (idx * 4));
 	if (!ignore_en && !(sctl & 0x00000100))
 		return 0;

 	/* out_alt */
 	if (sctl & 0x00000400)
 		return 108000;

 	/* vco_out */
 	switch (sctl & 0x00003000) {
 	case 0x00000000:
 		if (!(sctl & 0x00000200))
 			return device->crystal;
 		return 0;
 	case 0x00002000:
 		if (sctl & 0x00000040)
 			return 108000;
 		return 100000;
 	case 0x00003000:
 		/* vco_enable */
 		if (!(sctl & 0x00000001))
 			return 0;

 		sclk = read_vco(clk, idx);
 		sdiv = ((sctl & 0x003f0000) >> 16) + 2;
 		return (sclk * 2) / sdiv;
 	default:
 		return 0;
 	}
 }

 static u32
 read_pll(struct gt215_clk *clk, int idx, u32 pll)
 {
 	struct nvkm_device *device = clk->base.subdev.device;
 	u32 ctrl = nvkm_rd32(device, pll + 0);
 	u32 sclk = 0, P = 1, N = 1, M = 1;

 	if (!(ctrl & 0x00000008)) {
 		if (ctrl & 0x00000001) {
 			u32 coef = nvkm_rd32(device, pll + 4);
 			M = (coef & 0x000000ff) >> 0;
 			N = (coef & 0x0000ff00) >> 8;
 			P = (coef & 0x003f0000) >> 16;

 			/* no post-divider on these..
 			 * XXX: it looks more like two post-"dividers" that
 			 * cross each other out in the default RPLL config */
 			if ((pll & 0x00ff00) == 0x00e800)
 				P = 1;

 			sclk = read_clk(clk, 0x00 + idx, false);
 		}
 	} else {
 		sclk = read_clk(clk, 0x10 + idx, false);
 	}

 	if (M * P)
 		return sclk * N / (M * P);

 	return 0;
 }

 static int
 gt215_clk_read(struct nvkm_clk *base, enum nv_clk_src src)
 {
 	struct gt215_clk *clk = gt215_clk(base);
 	struct nvkm_subdev *subdev = &clk->base.subdev;
 	struct nvkm_device *device = subdev->device;
 	u32 hsrc;

 	switch (src) {
 	case nv_clk_src_crystal:
 		return device->crystal;
 	case nv_clk_src_core:
 	case nv_clk_src_core_intm:
 		return read_pll(clk, 0x00, 0x4200);
 	case nv_clk_src_shader:
 		return read_pll(clk, 0x01, 0x4220);
 	case nv_clk_src_mem:
 		return read_pll(clk, 0x02, 0x4000);
 	case nv_clk_src_disp:
 		return read_clk(clk, 0x20, false);
 	case nv_clk_src_vdec:
 		return read_clk(clk, 0x21, false);
 	case nv_clk_src_pmu:
 		return read_clk(clk, 0x25, false);
 	case nv_clk_src_host:
 		hsrc = (nvkm_rd32(device, 0xc040) & 0x30000000) >> 28;
 		switch (hsrc) {
 		case 0:
 			return read_clk(clk, 0x1d, false);
 		case 2:
 		case 3:
 			return 277000;
 		default:
 			nvkm_error(subdev, "unknown HOST clock source %d\n", hsrc);
 			return -EINVAL;
 		}
 	default:
 		nvkm_error(subdev, "invalid clock source %d\n", src);
 		return -EINVAL;
 	}

 	return 0;
 }

 static int
 gt215_clk_info(struct nvkm_clk *base, int idx, u32 khz,
 	       struct gt215_clk_info *info)
 {
 	struct gt215_clk *clk = gt215_clk(base);
 	u32 oclk, sclk, sdiv;
 	s32 diff;

 	info->clk = 0;

 	switch (khz) {
 	case 27000:
 		info->clk = 0x00000100;
 		return khz;
 	case 100000:
 		info->clk = 0x00002100;
 		return khz;
 	case 108000:
 		info->clk = 0x00002140;
 		return khz;
 	default:
 		sclk = read_vco(clk, idx);
 		sdiv = min((sclk * 2) / khz, (u32)65);
 		oclk = (sclk * 2) / sdiv;
 		diff = ((khz + 3000) - oclk);

 		/* When imprecise, play it safe and aim for a clock lower than
 		 * desired rather than higher */
 		if (diff < 0) {
 			sdiv++;
 			oclk = (sclk * 2) / sdiv;
 		}

 		/* divider can go as low as 2, limited here because NVIDIA
 		 * and the VBIOS on my NVA8 seem to prefer using the PLL
 		 * for 810MHz - is there a good reason?
 		 * XXX: PLLs with refclk 810MHz?  */
 		if (sdiv > 4) {
 			info->clk = (((sdiv - 2) << 16) | 0x00003100);
 			return oclk;
 		}

 		break;
 	}

 	return -ERANGE;
 }

 int
 gt215_pll_info(struct nvkm_clk *base, int idx, u32 pll, u32 khz,
 	       struct gt215_clk_info *info)
 {
 	struct gt215_clk *clk = gt215_clk(base);
 	struct nvkm_subdev *subdev = &clk->base.subdev;
 	struct nvbios_pll limits;
 	int P, N, M, diff;
 	int ret;

 	info->pll = 0;

 	/* If we can get a within [-2, 3) MHz of a divider, we'll disable the
 	 * PLL and use the divider instead. */
 	ret = gt215_clk_info(&clk->base, idx, khz, info);
 	diff = khz - ret;
 	if (!pll || (diff >= -2000 && diff < 3000)) {
 		goto out;
 	}

 	/* Try with PLL */
 	ret = nvbios_pll_parse(subdev->device->bios, pll, &limits);
 	if (ret)
 		return ret;

 	ret = gt215_clk_info(&clk->base, idx - 0x10, limits.refclk, info);
 	if (ret != limits.refclk)
 		return -EINVAL;

 	ret = gt215_pll_calc(subdev, &limits, khz, &N, NULL, &M, &P);
 	if (ret >= 0) {
 		info->pll = (P << 16) | (N << 8) | M;
 	}

 out:
 	info->fb_delay = max(((khz + 7566) / 15133), (u32) 18);
 	return ret ? ret : -ERANGE;
 }

 static int
 calc_clk(struct gt215_clk *clk, struct nvkm_cstate *cstate,
 	 int idx, u32 pll, int dom)
 {
 	int ret = gt215_pll_info(&clk->base, idx, pll, cstate->domain[dom],
 				 &clk->eng[dom]);
 	if (ret >= 0)
 		return 0;
 	return ret;
 }

 static int
 calc_host(struct gt215_clk *clk, struct nvkm_cstate *cstate)
 {
 	int ret = 0;
 	u32 kHz = cstate->domain[nv_clk_src_host];
 	struct gt215_clk_info *info = &clk->eng[nv_clk_src_host];

 	if (kHz == 277000) {
 		info->clk = 0;
 		info->host_out = NVA3_HOST_277;
 		return 0;
 	}

 	info->host_out = NVA3_HOST_CLK;

 	ret = gt215_clk_info(&clk->base, 0x1d, kHz, info);
 	if (ret >= 0)
 		return 0;

 	return ret;
 }

 int
 gt215_clk_pre(struct nvkm_clk *clk, unsigned long *flags)
 {
 	struct nvkm_device *device = clk->subdev.device;
 	struct nvkm_fifo *fifo = device->fifo;

 	/* halt and idle execution engines */
 	nvkm_mask(device, 0x020060, 0x00070000, 0x00000000);
 	nvkm_mask(device, 0x002504, 0x00000001, 0x00000001);
 	/* Wait until the interrupt handler is finished */
 	if (nvkm_msec(device, 2000,
 		if (!nvkm_rd32(device, 0x000100))
 			break;
 	) < 0)
 		return -EBUSY;

 	if (fifo)
 		nvkm_fifo_pause(fifo, flags);

 	if (nvkm_msec(device, 2000,
 		if (nvkm_rd32(device, 0x002504) & 0x00000010)
 			break;
 	) < 0)
 		return -EIO;

 	if (nvkm_msec(device, 2000,
 		u32 tmp = nvkm_rd32(device, 0x00251c) & 0x0000003f;
 		if (tmp == 0x0000003f)
 			break;
 	) < 0)
 		return -EIO;

 	return 0;
 }

 void
 gt215_clk_post(struct nvkm_clk *clk, unsigned long *flags)
 {
 	struct nvkm_device *device = clk->subdev.device;
 	struct nvkm_fifo *fifo = device->fifo;

 	if (fifo && flags)
 		nvkm_fifo_start(fifo, flags);

 	nvkm_mask(device, 0x002504, 0x00000001, 0x00000000);
 	nvkm_mask(device, 0x020060, 0x00070000, 0x00040000);
 }

 static void
 disable_clk_src(struct gt215_clk *clk, u32 src)
 {
 	struct nvkm_device *device = clk->base.subdev.device;
 	nvkm_mask(device, src, 0x00000100, 0x00000000);
 	nvkm_mask(device, src, 0x00000001, 0x00000000);
 }

 static void
 prog_pll(struct gt215_clk *clk, int idx, u32 pll, int dom)
 {
 	struct gt215_clk_info *info = &clk->eng[dom];
 	struct nvkm_device *device = clk->base.subdev.device;
 	const u32 src0 = 0x004120 + (idx * 4);
 	const u32 src1 = 0x004160 + (idx * 4);
 	const u32 ctrl = pll + 0;
 	const u32 coef = pll + 4;
 	u32 bypass;

 	if (info->pll) {
 		/* Always start from a non-PLL clock */
 		bypass = nvkm_rd32(device, ctrl)  & 0x00000008;
 		if (!bypass) {
 			nvkm_mask(device, src1, 0x00000101, 0x00000101);
 			nvkm_mask(device, ctrl, 0x00000008, 0x00000008);
 			udelay(20);
 		}

 		nvkm_mask(device, src0, 0x003f3141, 0x00000101 | info->clk);
 		nvkm_wr32(device, coef, info->pll);
 		nvkm_mask(device, ctrl, 0x00000015, 0x00000015);
 		nvkm_mask(device, ctrl, 0x00000010, 0x00000000);
 		if (nvkm_msec(device, 2000,
 			if (nvkm_rd32(device, ctrl) & 0x00020000)
 				break;
 		) < 0) {
 			nvkm_mask(device, ctrl, 0x00000010, 0x00000010);
 			nvkm_mask(device, src0, 0x00000101, 0x00000000);
 			return;
 		}
 		nvkm_mask(device, ctrl, 0x00000010, 0x00000010);
 		nvkm_mask(device, ctrl, 0x00000008, 0x00000000);
 		disable_clk_src(clk, src1);
 	} else {
 		nvkm_mask(device, src1, 0x003f3141, 0x00000101 | info->clk);
 		nvkm_mask(device, ctrl, 0x00000018, 0x00000018);
 		udelay(20);
 		nvkm_mask(device, ctrl, 0x00000001, 0x00000000);
 		disable_clk_src(clk, src0);
 	}
 }

 static void
 prog_clk(struct gt215_clk *clk, int idx, int dom)
 {
 	struct gt215_clk_info *info = &clk->eng[dom];
 	struct nvkm_device *device = clk->base.subdev.device;
 	nvkm_mask(device, 0x004120 + (idx * 4), 0x003f3141, 0x00000101 | info->clk);
 }

 static void
 prog_host(struct gt215_clk *clk)
 {
 	struct gt215_clk_info *info = &clk->eng[nv_clk_src_host];
 	struct nvkm_device *device = clk->base.subdev.device;
 	u32 hsrc = (nvkm_rd32(device, 0xc040));

 	switch (info->host_out) {
 	case NVA3_HOST_277:
 		if ((hsrc & 0x30000000) == 0) {
 			nvkm_wr32(device, 0xc040, hsrc | 0x20000000);
 			disable_clk_src(clk, 0x4194);
 		}
 		break;
 	case NVA3_HOST_CLK:
 		prog_clk(clk, 0x1d, nv_clk_src_host);
 		if ((hsrc & 0x30000000) >= 0x20000000) {
 			nvkm_wr32(device, 0xc040, hsrc & ~0x30000000);
 		}
 		break;
 	default:
 		break;
 	}

 	/* This seems to be a clock gating factor on idle, always set to 64 */
 	nvkm_wr32(device, 0xc044, 0x3e);
 }

 static void
 prog_core(struct gt215_clk *clk, int dom)
 {
 	struct gt215_clk_info *info = &clk->eng[dom];
 	struct nvkm_device *device = clk->base.subdev.device;
 	u32 fb_delay = nvkm_rd32(device, 0x10002c);

 	if (fb_delay < info->fb_delay)
 		nvkm_wr32(device, 0x10002c, info->fb_delay);

 	prog_pll(clk, 0x00, 0x004200, dom);

 	if (fb_delay > info->fb_delay)
 		nvkm_wr32(device, 0x10002c, info->fb_delay);
 }

 static int
 gt215_clk_calc(struct nvkm_clk *base, struct nvkm_cstate *cstate)
 {
 	struct gt215_clk *clk = gt215_clk(base);
 	struct gt215_clk_info *core = &clk->eng[nv_clk_src_core];
 	int ret;

 	if ((ret = calc_clk(clk, cstate, 0x10, 0x4200, nv_clk_src_core)) ||
 	    (ret = calc_clk(clk, cstate, 0x11, 0x4220, nv_clk_src_shader)) ||
 	    (ret = calc_clk(clk, cstate, 0x20, 0x0000, nv_clk_src_disp)) ||
 	    (ret = calc_clk(clk, cstate, 0x21, 0x0000, nv_clk_src_vdec)) ||
 	    (ret = calc_host(clk, cstate)))
 		return ret;

 	/* XXX: Should be reading the highest bit in the VBIOS clock to decide
 	 * whether to use a PLL or not... but using a PLL defeats the purpose */
 	if (core->pll) {
 		ret = gt215_clk_info(&clk->base, 0x10,
 				     cstate->domain[nv_clk_src_core_intm],
 				     &clk->eng[nv_clk_src_core_intm]);
 		if (ret < 0)
 			return ret;
 	}

 	return 0;
 }

 static int
 gt215_clk_prog(struct nvkm_clk *base)
 {
 	struct gt215_clk *clk = gt215_clk(base);
 	struct gt215_clk_info *core = &clk->eng[nv_clk_src_core];
 	int ret = 0;
 	unsigned long flags;
 	unsigned long *f = &flags;

 	ret = gt215_clk_pre(&clk->base, f);
 	if (ret)
 		goto out;

 	if (core->pll)
 		prog_core(clk, nv_clk_src_core_intm);

 	prog_core(clk,  nv_clk_src_core);
 	prog_pll(clk, 0x01, 0x004220, nv_clk_src_shader);
 	prog_clk(clk, 0x20, nv_clk_src_disp);
 	prog_clk(clk, 0x21, nv_clk_src_vdec);
 	prog_host(clk);

 out:
 	if (ret == -EBUSY)
 		f = NULL;

 	gt215_clk_post(&clk->base, f);
 	return ret;
 }

 static void
 gt215_clk_tidy(struct nvkm_clk *base)
 {
 }

 static const struct nvkm_clk_func
 gt215_clk = {
 	.read = gt215_clk_read,
 	.calc = gt215_clk_calc,
 	.prog = gt215_clk_prog,
 	.tidy = gt215_clk_tidy,
 	.domains = {
 		{ nv_clk_src_crystal  , 0xff },
 		{ nv_clk_src_core     , 0x00, 0, "core", 1000 },
 		{ nv_clk_src_shader   , 0x01, 0, "shader", 1000 },
 		{ nv_clk_src_mem      , 0x02, 0, "memory", 1000 },
 		{ nv_clk_src_vdec     , 0x03 },
 		{ nv_clk_src_disp     , 0x04 },
 		{ nv_clk_src_host     , 0x05 },
 		{ nv_clk_src_core_intm, 0x06 },
 		{ nv_clk_src_max }
 	}
 };

 int
 gt215_clk_new(struct nvkm_device *device, int index, struct nvkm_clk **pclk)
 {
 	struct gt215_clk *clk;

 	if (!(clk = kzalloc(sizeof(*clk), GFP_KERNEL)))
 		return -ENOMEM;
 	*pclk = &clk->base;

 	return nvkm_clk_ctor(&gt215_clk, device, index, true, &clk->base);
 }
	/*
	* Copyright 2012 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
	* Roy Spliet
	*/
	#define gt215_clk(p) container_of((p), struct gt215_clk, base)
	#include "gt215.h"
	#include "pll.h"

	#include <engine/fifo.h>
	#include <subdev/bios.h>
	#include <subdev/bios/pll.h>
	#include <subdev/timer.h>

	struct gt215_clk {
	struct nvkm_clk base;
	struct gt215_clk_info eng[nv_clk_src_max];
	};

	static u32 read_clk(struct gt215_clk *, int, bool);
	static u32 read_pll(struct gt215_clk *, int, u32);

	static u32
	read_vco(struct gt215_clk *clk, int idx)
	{
	struct nvkm_device *device = clk->base.subdev.device;
	u32 sctl = nvkm_rd32(device, 0x4120 + (idx * 4));

	switch (sctl & 0x00000030) {
	case 0x00000000:
	return device->crystal;
	case 0x00000020:
	return read_pll(clk, 0x41, 0x00e820);
	case 0x00000030:
	return read_pll(clk, 0x42, 0x00e8a0);
	default:
	return 0;
	}
	}

	static u32
	read_clk(struct gt215_clk *clk, int idx, bool ignore_en)
	{
	struct nvkm_device *device = clk->base.subdev.device;
	u32 sctl, sdiv, sclk;

	/* refclk for the 0xe8xx plls is a fixed frequency */
	if (idx >= 0x40) {
	if (device->chipset == 0xaf) {
	/* no joke.. seriously.. sigh.. */
	return nvkm_rd32(device, 0x00471c) * 1000;
	}

	return device->crystal;
	}

	sctl = nvkm_rd32(device, 0x4120 + (idx * 4));
	if (!ignore_en && !(sctl & 0x00000100))
	return 0;

	/* out_alt */
	if (sctl & 0x00000400)
	return 108000;

	/* vco_out */
	switch (sctl & 0x00003000) {
	case 0x00000000:
	if (!(sctl & 0x00000200))
	return device->crystal;
	return 0;
	case 0x00002000:
	if (sctl & 0x00000040)
	return 108000;
	return 100000;
	case 0x00003000:
	/* vco_enable */
	if (!(sctl & 0x00000001))
	return 0;

	sclk = read_vco(clk, idx);
	sdiv = ((sctl & 0x003f0000) >> 16) + 2;
	return (sclk * 2) / sdiv;
	default:
	return 0;
	}
	}

	static u32
	read_pll(struct gt215_clk *clk, int idx, u32 pll)
	{
	struct nvkm_device *device = clk->base.subdev.device;
	u32 ctrl = nvkm_rd32(device, pll + 0);
	u32 sclk = 0, P = 1, N = 1, M = 1;

	if (!(ctrl & 0x00000008)) {
	if (ctrl & 0x00000001) {
	u32 coef = nvkm_rd32(device, pll + 4);
	M = (coef & 0x000000ff) >> 0;
	N = (coef & 0x0000ff00) >> 8;
	P = (coef & 0x003f0000) >> 16;

	/* no post-divider on these..
	* XXX: it looks more like two post-"dividers" that
	* cross each other out in the default RPLL config */
	if ((pll & 0x00ff00) == 0x00e800)
	P = 1;

	sclk = read_clk(clk, 0x00 + idx, false);
	}
	} else {
	sclk = read_clk(clk, 0x10 + idx, false);
	}

	if (M * P)
	return sclk * N / (M * P);

	return 0;
	}

	static int
	gt215_clk_read(struct nvkm_clk *base, enum nv_clk_src src)
	{
	struct gt215_clk *clk = gt215_clk(base);
	struct nvkm_subdev *subdev = &clk->base.subdev;
	struct nvkm_device *device = subdev->device;
	u32 hsrc;

	switch (src) {
	case nv_clk_src_crystal:
	return device->crystal;
	case nv_clk_src_core:
	case nv_clk_src_core_intm:
	return read_pll(clk, 0x00, 0x4200);
	case nv_clk_src_shader:
	return read_pll(clk, 0x01, 0x4220);
	case nv_clk_src_mem:
	return read_pll(clk, 0x02, 0x4000);
	case nv_clk_src_disp:
	return read_clk(clk, 0x20, false);
	case nv_clk_src_vdec:
	return read_clk(clk, 0x21, false);
	case nv_clk_src_pmu:
	return read_clk(clk, 0x25, false);
	case nv_clk_src_host:
	hsrc = (nvkm_rd32(device, 0xc040) & 0x30000000) >> 28;
	switch (hsrc) {
	case 0:
	return read_clk(clk, 0x1d, false);
	case 2:
	case 3:
	return 277000;
	default:
	nvkm_error(subdev, "unknown HOST clock source %d\n", hsrc);
	return -EINVAL;
	}
	default:
	nvkm_error(subdev, "invalid clock source %d\n", src);
	return -EINVAL;
	}

	return 0;
	}

	static int
	gt215_clk_info(struct nvkm_clk *base, int idx, u32 khz,
	struct gt215_clk_info *info)
	{
	struct gt215_clk *clk = gt215_clk(base);
	u32 oclk, sclk, sdiv;
	s32 diff;

	info->clk = 0;

	switch (khz) {
	case 27000:
	info->clk = 0x00000100;
	return khz;
	case 100000:
	info->clk = 0x00002100;
	return khz;
	case 108000:
	info->clk = 0x00002140;
	return khz;
	default:
	sclk = read_vco(clk, idx);
	sdiv = min((sclk * 2) / khz, (u32)65);
	oclk = (sclk * 2) / sdiv;
	diff = ((khz + 3000) - oclk);

	/* When imprecise, play it safe and aim for a clock lower than
	* desired rather than higher */
	if (diff < 0) {
	sdiv++;
	oclk = (sclk * 2) / sdiv;
	}

	/* divider can go as low as 2, limited here because NVIDIA
	* and the VBIOS on my NVA8 seem to prefer using the PLL
	* for 810MHz - is there a good reason?
	* XXX: PLLs with refclk 810MHz? */
	if (sdiv > 4) {
	info->clk = (((sdiv - 2) << 16) \| 0x00003100);
	return oclk;
	}

	break;
	}

	return -ERANGE;
	}

	int
	gt215_pll_info(struct nvkm_clk *base, int idx, u32 pll, u32 khz,
	struct gt215_clk_info *info)
	{
	struct gt215_clk *clk = gt215_clk(base);
	struct nvkm_subdev *subdev = &clk->base.subdev;
	struct nvbios_pll limits;
	int P, N, M, diff;
	int ret;

	info->pll = 0;

	/* If we can get a within [-2, 3) MHz of a divider, we'll disable the
	* PLL and use the divider instead. */
	ret = gt215_clk_info(&clk->base, idx, khz, info);
	diff = khz - ret;
	if (!pll \|\| (diff >= -2000 && diff < 3000)) {
	goto out;
	}

	/* Try with PLL */
	ret = nvbios_pll_parse(subdev->device->bios, pll, &limits);
	if (ret)
	return ret;

	ret = gt215_clk_info(&clk->base, idx - 0x10, limits.refclk, info);
	if (ret != limits.refclk)
	return -EINVAL;

	ret = gt215_pll_calc(subdev, &limits, khz, &N, NULL, &M, &P);
	if (ret >= 0) {
	info->pll = (P << 16) \| (N << 8) \| M;
	}

	out:
	info->fb_delay = max(((khz + 7566) / 15133), (u32) 18);
	return ret ? ret : -ERANGE;
	}

	static int
	calc_clk(struct gt215_clk clk, struct nvkm_cstate cstate,
	int idx, u32 pll, int dom)
	{
	int ret = gt215_pll_info(&clk->base, idx, pll, cstate->domain[dom],
	&clk->eng[dom]);
	if (ret >= 0)
	return 0;
	return ret;
	}

	static int
	calc_host(struct gt215_clk clk, struct nvkm_cstate cstate)
	{
	int ret = 0;
	u32 kHz = cstate->domain[nv_clk_src_host];
	struct gt215_clk_info *info = &clk->eng[nv_clk_src_host];

	if (kHz == 277000) {
	info->clk = 0;
	info->host_out = NVA3_HOST_277;
	return 0;
	}

	info->host_out = NVA3_HOST_CLK;

	ret = gt215_clk_info(&clk->base, 0x1d, kHz, info);
	if (ret >= 0)
	return 0;

	return ret;
	}

	int
	gt215_clk_pre(struct nvkm_clk clk, unsigned long flags)
	{
	struct nvkm_device *device = clk->subdev.device;
	struct nvkm_fifo *fifo = device->fifo;

	/* halt and idle execution engines */
	nvkm_mask(device, 0x020060, 0x00070000, 0x00000000);
	nvkm_mask(device, 0x002504, 0x00000001, 0x00000001);
	/* Wait until the interrupt handler is finished */
	if (nvkm_msec(device, 2000,
	if (!nvkm_rd32(device, 0x000100))
	break;
	) < 0)
	return -EBUSY;

	if (fifo)
	nvkm_fifo_pause(fifo, flags);

	if (nvkm_msec(device, 2000,
	if (nvkm_rd32(device, 0x002504) & 0x00000010)
	break;
	) < 0)
	return -EIO;

	if (nvkm_msec(device, 2000,
	u32 tmp = nvkm_rd32(device, 0x00251c) & 0x0000003f;
	if (tmp == 0x0000003f)
	break;
	) < 0)
	return -EIO;

	return 0;
	}

	void
	gt215_clk_post(struct nvkm_clk clk, unsigned long flags)
	{
	struct nvkm_device *device = clk->subdev.device;
	struct nvkm_fifo *fifo = device->fifo;

	if (fifo && flags)
	nvkm_fifo_start(fifo, flags);

	nvkm_mask(device, 0x002504, 0x00000001, 0x00000000);
	nvkm_mask(device, 0x020060, 0x00070000, 0x00040000);
	}

	static void
	disable_clk_src(struct gt215_clk *clk, u32 src)
	{
	struct nvkm_device *device = clk->base.subdev.device;
	nvkm_mask(device, src, 0x00000100, 0x00000000);
	nvkm_mask(device, src, 0x00000001, 0x00000000);
	}

	static void
	prog_pll(struct gt215_clk *clk, int idx, u32 pll, int dom)
	{
	struct gt215_clk_info *info = &clk->eng[dom];
	struct nvkm_device *device = clk->base.subdev.device;
	const u32 src0 = 0x004120 + (idx * 4);
	const u32 src1 = 0x004160 + (idx * 4);
	const u32 ctrl = pll + 0;
	const u32 coef = pll + 4;
	u32 bypass;

	if (info->pll) {
	/* Always start from a non-PLL clock */
	bypass = nvkm_rd32(device, ctrl) & 0x00000008;
	if (!bypass) {
	nvkm_mask(device, src1, 0x00000101, 0x00000101);
	nvkm_mask(device, ctrl, 0x00000008, 0x00000008);
	udelay(20);
	}

	nvkm_mask(device, src0, 0x003f3141, 0x00000101 \| info->clk);
	nvkm_wr32(device, coef, info->pll);
	nvkm_mask(device, ctrl, 0x00000015, 0x00000015);
	nvkm_mask(device, ctrl, 0x00000010, 0x00000000);
	if (nvkm_msec(device, 2000,
	if (nvkm_rd32(device, ctrl) & 0x00020000)
	break;
	) < 0) {
	nvkm_mask(device, ctrl, 0x00000010, 0x00000010);
	nvkm_mask(device, src0, 0x00000101, 0x00000000);
	return;
	}
	nvkm_mask(device, ctrl, 0x00000010, 0x00000010);
	nvkm_mask(device, ctrl, 0x00000008, 0x00000000);
	disable_clk_src(clk, src1);
	} else {
	nvkm_mask(device, src1, 0x003f3141, 0x00000101 \| info->clk);
	nvkm_mask(device, ctrl, 0x00000018, 0x00000018);
	udelay(20);
	nvkm_mask(device, ctrl, 0x00000001, 0x00000000);
	disable_clk_src(clk, src0);
	}
	}

	static void
	prog_clk(struct gt215_clk *clk, int idx, int dom)
	{
	struct gt215_clk_info *info = &clk->eng[dom];
	struct nvkm_device *device = clk->base.subdev.device;
	nvkm_mask(device, 0x004120 + (idx * 4), 0x003f3141, 0x00000101 \| info->clk);
	}

	static void
	prog_host(struct gt215_clk *clk)
	{
	struct gt215_clk_info *info = &clk->eng[nv_clk_src_host];
	struct nvkm_device *device = clk->base.subdev.device;
	u32 hsrc = (nvkm_rd32(device, 0xc040));

	switch (info->host_out) {
	case NVA3_HOST_277:
	if ((hsrc & 0x30000000) == 0) {
	nvkm_wr32(device, 0xc040, hsrc \| 0x20000000);
	disable_clk_src(clk, 0x4194);
	}
	break;
	case NVA3_HOST_CLK:
	prog_clk(clk, 0x1d, nv_clk_src_host);
	if ((hsrc & 0x30000000) >= 0x20000000) {
	nvkm_wr32(device, 0xc040, hsrc & ~0x30000000);
	}
	break;
	default:
	break;
	}

	/* This seems to be a clock gating factor on idle, always set to 64 */
	nvkm_wr32(device, 0xc044, 0x3e);
	}

	static void
	prog_core(struct gt215_clk *clk, int dom)
	{
	struct gt215_clk_info *info = &clk->eng[dom];
	struct nvkm_device *device = clk->base.subdev.device;
	u32 fb_delay = nvkm_rd32(device, 0x10002c);

	if (fb_delay < info->fb_delay)
	nvkm_wr32(device, 0x10002c, info->fb_delay);

	prog_pll(clk, 0x00, 0x004200, dom);

	if (fb_delay > info->fb_delay)
	nvkm_wr32(device, 0x10002c, info->fb_delay);
	}

	static int
	gt215_clk_calc(struct nvkm_clk base, struct nvkm_cstate cstate)
	{
	struct gt215_clk *clk = gt215_clk(base);
	struct gt215_clk_info *core = &clk->eng[nv_clk_src_core];
	int ret;

	if ((ret = calc_clk(clk, cstate, 0x10, 0x4200, nv_clk_src_core)) \|\|
	(ret = calc_clk(clk, cstate, 0x11, 0x4220, nv_clk_src_shader)) \|\|
	(ret = calc_clk(clk, cstate, 0x20, 0x0000, nv_clk_src_disp)) \|\|
	(ret = calc_clk(clk, cstate, 0x21, 0x0000, nv_clk_src_vdec)) \|\|
	(ret = calc_host(clk, cstate)))
	return ret;

	/* XXX: Should be reading the highest bit in the VBIOS clock to decide
	* whether to use a PLL or not... but using a PLL defeats the purpose */
	if (core->pll) {
	ret = gt215_clk_info(&clk->base, 0x10,
	cstate->domain[nv_clk_src_core_intm],
	&clk->eng[nv_clk_src_core_intm]);
	if (ret < 0)
	return ret;
	}

	return 0;
	}

	static int
	gt215_clk_prog(struct nvkm_clk *base)
	{
	struct gt215_clk *clk = gt215_clk(base);
	struct gt215_clk_info *core = &clk->eng[nv_clk_src_core];
	int ret = 0;
	unsigned long flags;
	unsigned long *f = &flags;

	ret = gt215_clk_pre(&clk->base, f);
	if (ret)
	goto out;

	if (core->pll)
	prog_core(clk, nv_clk_src_core_intm);

	prog_core(clk, nv_clk_src_core);
	prog_pll(clk, 0x01, 0x004220, nv_clk_src_shader);
	prog_clk(clk, 0x20, nv_clk_src_disp);
	prog_clk(clk, 0x21, nv_clk_src_vdec);
	prog_host(clk);

	out:
	if (ret == -EBUSY)
	f = NULL;

	gt215_clk_post(&clk->base, f);
	return ret;
	}

	static void
	gt215_clk_tidy(struct nvkm_clk *base)
	{
	}

	static const struct nvkm_clk_func
	gt215_clk = {
	.read = gt215_clk_read,
	.calc = gt215_clk_calc,
	.prog = gt215_clk_prog,
	.tidy = gt215_clk_tidy,
	.domains = {
	{ nv_clk_src_crystal , 0xff },
	{ nv_clk_src_core , 0x00, 0, "core", 1000 },
	{ nv_clk_src_shader , 0x01, 0, "shader", 1000 },
	{ nv_clk_src_mem , 0x02, 0, "memory", 1000 },
	{ nv_clk_src_vdec , 0x03 },
	{ nv_clk_src_disp , 0x04 },
	{ nv_clk_src_host , 0x05 },
	{ nv_clk_src_core_intm, 0x06 },
	{ nv_clk_src_max }
	}
	};

	int
	gt215_clk_new(struct nvkm_device device, int index, struct nvkm_clk *pclk)
	{
	struct gt215_clk *clk;

	if (!(clk = kzalloc(sizeof(*clk), GFP_KERNEL)))
	return -ENOMEM;
	*pclk = &clk->base;

	return nvkm_clk_ctor(&gt215_clk, device, index, true, &clk->base);
	}