drm/nouveau: Add DRM driver for NVIDIA GPUs

This adds a drm/kms staging non-API stable driver for GPUs from NVIDIA.

This driver is a KMS-based driver and requires a compatible nouveau
userspace libdrm and nouveau X.org driver.

This driver requires firmware files not available in this kernel tree,
interested parties can find them via the nouveau project git archive.

This driver is reverse engineered, and is in no way supported by nVidia.

Support for nearly the complete range of nvidia hw from nv04->g80 (nv50)
is available, and the kms driver should support driving nearly all
output types (displayport is under development still) along with supporting
suspend/resume.

This work is all from the upstream nouveau project found at
nouveau.freedesktop.org.

The original authors list from nouveau git tree is:
Anssi Hannula <anssi.hannula@iki.fi>
Ben Skeggs <bskeggs@redhat.com>
Francisco Jerez <currojerez@riseup.net>
Maarten Maathuis <madman2003@gmail.com>
Marcin Koƛcielnicki <koriakin@0x04.net>
Matthew Garrett <mjg@redhat.com>
Matt Parnell <mparnell@gmail.com>
Patrice Mandin <patmandin@gmail.com>
Pekka Paalanen <pq@iki.fi>
Xavier Chantry <shiningxc@gmail.com>
along with project founder Stephane Marchesin <marchesin@icps.u-strasbg.fr>

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_calc.c b/drivers/gpu/drm/nouveau/nouveau_calc.c
new file mode 100644
index 0000000..ee2b845
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nouveau_calc.c
@@ -0,0 +1,478 @@
+/*
+ * Copyright 1993-2003 NVIDIA, Corporation
+ * Copyright 2007-2009 Stuart Bennett
+ *
+ * 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 AUTHORS 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.
+ */
+
+#include "drmP.h"
+#include "nouveau_drv.h"
+#include "nouveau_hw.h"
+
+/****************************************************************************\
+*                                                                            *
+* The video arbitration routines calculate some "magic" numbers.  Fixes      *
+* the snow seen when accessing the framebuffer without it.                   *
+* It just works (I hope).                                                    *
+*                                                                            *
+\****************************************************************************/
+
+struct nv_fifo_info {
+	int lwm;
+	int burst;
+};
+
+struct nv_sim_state {
+	int pclk_khz;
+	int mclk_khz;
+	int nvclk_khz;
+	int bpp;
+	int mem_page_miss;
+	int mem_latency;
+	int memory_type;
+	int memory_width;
+	int two_heads;
+};
+
+static void
+nv04_calc_arb(struct nv_fifo_info *fifo, struct nv_sim_state *arb)
+{
+	int pagemiss, cas, width, bpp;
+	int nvclks, mclks, pclks, crtpagemiss;
+	int found, mclk_extra, mclk_loop, cbs, m1, p1;
+	int mclk_freq, pclk_freq, nvclk_freq;
+	int us_m, us_n, us_p, crtc_drain_rate;
+	int cpm_us, us_crt, clwm;
+
+	pclk_freq = arb->pclk_khz;
+	mclk_freq = arb->mclk_khz;
+	nvclk_freq = arb->nvclk_khz;
+	pagemiss = arb->mem_page_miss;
+	cas = arb->mem_latency;
+	width = arb->memory_width >> 6;
+	bpp = arb->bpp;
+	cbs = 128;
+
+	pclks = 2;
+	nvclks = 10;
+	mclks = 13 + cas;
+	mclk_extra = 3;
+	found = 0;
+
+	while (!found) {
+		found = 1;
+
+		mclk_loop = mclks + mclk_extra;
+		us_m = mclk_loop * 1000 * 1000 / mclk_freq;
+		us_n = nvclks * 1000 * 1000 / nvclk_freq;
+		us_p = nvclks * 1000 * 1000 / pclk_freq;
+
+		crtc_drain_rate = pclk_freq * bpp / 8;
+		crtpagemiss = 2;
+		crtpagemiss += 1;
+		cpm_us = crtpagemiss * pagemiss * 1000 * 1000 / mclk_freq;
+		us_crt = cpm_us + us_m + us_n + us_p;
+		clwm = us_crt * crtc_drain_rate / (1000 * 1000);
+		clwm++;
+
+		m1 = clwm + cbs - 512;
+		p1 = m1 * pclk_freq / mclk_freq;
+		p1 = p1 * bpp / 8;
+		if ((p1 < m1 && m1 > 0) || clwm > 519) {
+			found = !mclk_extra;
+			mclk_extra--;
+		}
+		if (clwm < 384)
+			clwm = 384;
+
+		fifo->lwm = clwm;
+		fifo->burst = cbs;
+	}
+}
+
+static void
+nv10_calc_arb(struct nv_fifo_info *fifo, struct nv_sim_state *arb)
+{
+	int fill_rate, drain_rate;
+	int pclks, nvclks, mclks, xclks;
+	int pclk_freq, nvclk_freq, mclk_freq;
+	int fill_lat, extra_lat;
+	int max_burst_o, max_burst_l;
+	int fifo_len, min_lwm, max_lwm;
+	const int burst_lat = 80; /* Maximum allowable latency due
+				   * to the CRTC FIFO burst. (ns) */
+
+	pclk_freq = arb->pclk_khz;
+	nvclk_freq = arb->nvclk_khz;
+	mclk_freq = arb->mclk_khz;
+
+	fill_rate = mclk_freq * arb->memory_width / 8; /* kB/s */
+	drain_rate = pclk_freq * arb->bpp / 8; /* kB/s */
+
+	fifo_len = arb->two_heads ? 1536 : 1024; /* B */
+
+	/* Fixed FIFO refill latency. */
+
+	pclks = 4;	/* lwm detect. */
+
+	nvclks = 3	/* lwm -> sync. */
+		+ 2	/* fbi bus cycles (1 req + 1 busy) */
+		+ 1	/* 2 edge sync.  may be very close to edge so
+			 * just put one. */
+		+ 1	/* fbi_d_rdv_n */
+		+ 1	/* Fbi_d_rdata */
+		+ 1;	/* crtfifo load */
+
+	mclks = 1	/* 2 edge sync.  may be very close to edge so
+			 * just put one. */
+		+ 1	/* arb_hp_req */
+		+ 5	/* tiling pipeline */
+		+ 2	/* latency fifo */
+		+ 2	/* memory request to fbio block */
+		+ 7;	/* data returned from fbio block */
+
+	/* Need to accumulate 256 bits for read */
+	mclks += (arb->memory_type == 0 ? 2 : 1)
+		* arb->memory_width / 32;
+
+	fill_lat = mclks * 1000 * 1000 / mclk_freq   /* minimum mclk latency */
+		+ nvclks * 1000 * 1000 / nvclk_freq  /* nvclk latency */
+		+ pclks * 1000 * 1000 / pclk_freq;   /* pclk latency */
+
+	/* Conditional FIFO refill latency. */
+
+	xclks = 2 * arb->mem_page_miss + mclks /* Extra latency due to
+						* the overlay. */
+		+ 2 * arb->mem_page_miss       /* Extra pagemiss latency. */
+		+ (arb->bpp == 32 ? 8 : 4);    /* Margin of error. */
+
+	extra_lat = xclks * 1000 * 1000 / mclk_freq;
+
+	if (arb->two_heads)
+		/* Account for another CRTC. */
+		extra_lat += fill_lat + extra_lat + burst_lat;
+
+	/* FIFO burst */
+
+	/* Max burst not leading to overflows. */
+	max_burst_o = (1 + fifo_len - extra_lat * drain_rate / (1000 * 1000))
+		* (fill_rate / 1000) / ((fill_rate - drain_rate) / 1000);
+	fifo->burst = min(max_burst_o, 1024);
+
+	/* Max burst value with an acceptable latency. */
+	max_burst_l = burst_lat * fill_rate / (1000 * 1000);
+	fifo->burst = min(max_burst_l, fifo->burst);
+
+	fifo->burst = rounddown_pow_of_two(fifo->burst);
+
+	/* FIFO low watermark */
+
+	min_lwm = (fill_lat + extra_lat) * drain_rate / (1000 * 1000) + 1;
+	max_lwm = fifo_len - fifo->burst
+		+ fill_lat * drain_rate / (1000 * 1000)
+		+ fifo->burst * drain_rate / fill_rate;
+
+	fifo->lwm = min_lwm + 10 * (max_lwm - min_lwm) / 100; /* Empirical. */
+}
+
+static void
+nv04_update_arb(struct drm_device *dev, int VClk, int bpp,
+		int *burst, int *lwm)
+{
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	struct nv_fifo_info fifo_data;
+	struct nv_sim_state sim_data;
+	int MClk = nouveau_hw_get_clock(dev, MPLL);
+	int NVClk = nouveau_hw_get_clock(dev, NVPLL);
+	uint32_t cfg1 = nvReadFB(dev, NV_PFB_CFG1);
+
+	sim_data.pclk_khz = VClk;
+	sim_data.mclk_khz = MClk;
+	sim_data.nvclk_khz = NVClk;
+	sim_data.bpp = bpp;
+	sim_data.two_heads = nv_two_heads(dev);
+	if ((dev->pci_device & 0xffff) == 0x01a0 /*CHIPSET_NFORCE*/ ||
+	    (dev->pci_device & 0xffff) == 0x01f0 /*CHIPSET_NFORCE2*/) {
+		uint32_t type;
+
+		pci_read_config_dword(pci_get_bus_and_slot(0, 1), 0x7c, &type);
+
+		sim_data.memory_type = (type >> 12) & 1;
+		sim_data.memory_width = 64;
+		sim_data.mem_latency = 3;
+		sim_data.mem_page_miss = 10;
+	} else {
+		sim_data.memory_type = nvReadFB(dev, NV_PFB_CFG0) & 0x1;
+		sim_data.memory_width = (nvReadEXTDEV(dev, NV_PEXTDEV_BOOT_0) & 0x10) ? 128 : 64;
+		sim_data.mem_latency = cfg1 & 0xf;
+		sim_data.mem_page_miss = ((cfg1 >> 4) & 0xf) + ((cfg1 >> 31) & 0x1);
+	}
+
+	if (dev_priv->card_type == NV_04)
+		nv04_calc_arb(&fifo_data, &sim_data);
+	else
+		nv10_calc_arb(&fifo_data, &sim_data);
+
+	*burst = ilog2(fifo_data.burst >> 4);
+	*lwm = fifo_data.lwm >> 3;
+}
+
+static void
+nv30_update_arb(int *burst, int *lwm)
+{
+	unsigned int fifo_size, burst_size, graphics_lwm;
+
+	fifo_size = 2048;
+	burst_size = 512;
+	graphics_lwm = fifo_size - burst_size;
+
+	*burst = ilog2(burst_size >> 5);
+	*lwm = graphics_lwm >> 3;
+}
+
+void
+nouveau_calc_arb(struct drm_device *dev, int vclk, int bpp, int *burst, int *lwm)
+{
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+
+	if (dev_priv->card_type < NV_30)
+		nv04_update_arb(dev, vclk, bpp, burst, lwm);
+	else if ((dev->pci_device & 0xfff0) == 0x0240 /*CHIPSET_C51*/ ||
+		 (dev->pci_device & 0xfff0) == 0x03d0 /*CHIPSET_C512*/) {
+		*burst = 128;
+		*lwm = 0x0480;
+	} else
+		nv30_update_arb(burst, lwm);
+}
+
+static int
+getMNP_single(struct drm_device *dev, struct pll_lims *pll_lim, int clk,
+	      struct nouveau_pll_vals *bestpv)
+{
+	/* Find M, N and P for a single stage PLL
+	 *
+	 * Note that some bioses (NV3x) have lookup tables of precomputed MNP
+	 * values, but we're too lazy to use those atm
+	 *
+	 * "clk" parameter in kHz
+	 * returns calculated clock
+	 */
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	int cv = dev_priv->vbios->chip_version;
+	int minvco = pll_lim->vco1.minfreq, maxvco = pll_lim->vco1.maxfreq;
+	int minM = pll_lim->vco1.min_m, maxM = pll_lim->vco1.max_m;
+	int minN = pll_lim->vco1.min_n, maxN = pll_lim->vco1.max_n;
+	int minU = pll_lim->vco1.min_inputfreq;
+	int maxU = pll_lim->vco1.max_inputfreq;
+	int minP = pll_lim->max_p ? pll_lim->min_p : 0;
+	int maxP = pll_lim->max_p ? pll_lim->max_p : pll_lim->max_usable_log2p;
+	int crystal = pll_lim->refclk;
+	int M, N, thisP, P;
+	int clkP, calcclk;
+	int delta, bestdelta = INT_MAX;
+	int bestclk = 0;
+
+	/* this division verified for nv20, nv18, nv28 (Haiku), and nv34 */
+	/* possibly correlated with introduction of 27MHz crystal */
+	if (dev_priv->card_type < NV_50) {
+		if (cv < 0x17 || cv == 0x1a || cv == 0x20) {
+			if (clk > 250000)
+				maxM = 6;
+			if (clk > 340000)
+				maxM = 2;
+		} else if (cv < 0x40) {
+			if (clk > 150000)
+				maxM = 6;
+			if (clk > 200000)
+				maxM = 4;
+			if (clk > 340000)
+				maxM = 2;
+		}
+	}
+
+	P = pll_lim->max_p ? maxP : (1 << maxP);
+	if ((clk * P) < minvco) {
+		minvco = clk * maxP;
+		maxvco = minvco * 2;
+	}
+
+	if (clk + clk/200 > maxvco)	/* +0.5% */
+		maxvco = clk + clk/200;
+
+	/* NV34 goes maxlog2P->0, NV20 goes 0->maxlog2P */
+	for (thisP = minP; thisP <= maxP; thisP++) {
+		P = pll_lim->max_p ? thisP : (1 << thisP);
+		clkP = clk * P;
+
+		if (clkP < minvco)
+			continue;
+		if (clkP > maxvco)
+			return bestclk;
+
+		for (M = minM; M <= maxM; M++) {
+			if (crystal/M < minU)
+				return bestclk;
+			if (crystal/M > maxU)
+				continue;
+
+			/* add crystal/2 to round better */
+			N = (clkP * M + crystal/2) / crystal;
+
+			if (N < minN)
+				continue;
+			if (N > maxN)
+				break;
+
+			/* more rounding additions */
+			calcclk = ((N * crystal + P/2) / P + M/2) / M;
+			delta = abs(calcclk - clk);
+			/* we do an exhaustive search rather than terminating
+			 * on an optimality condition...
+			 */
+			if (delta < bestdelta) {
+				bestdelta = delta;
+				bestclk = calcclk;
+				bestpv->N1 = N;
+				bestpv->M1 = M;
+				bestpv->log2P = thisP;
+				if (delta == 0)	/* except this one */
+					return bestclk;
+			}
+		}
+	}
+
+	return bestclk;
+}
+
+static int
+getMNP_double(struct drm_device *dev, struct pll_lims *pll_lim, int clk,
+	      struct nouveau_pll_vals *bestpv)
+{
+	/* Find M, N and P for a two stage PLL
+	 *
+	 * Note that some bioses (NV30+) have lookup tables of precomputed MNP
+	 * values, but we're too lazy to use those atm
+	 *
+	 * "clk" parameter in kHz
+	 * returns calculated clock
+	 */
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	int chip_version = dev_priv->vbios->chip_version;
+	int minvco1 = pll_lim->vco1.minfreq, maxvco1 = pll_lim->vco1.maxfreq;
+	int minvco2 = pll_lim->vco2.minfreq, maxvco2 = pll_lim->vco2.maxfreq;
+	int minU1 = pll_lim->vco1.min_inputfreq, minU2 = pll_lim->vco2.min_inputfreq;
+	int maxU1 = pll_lim->vco1.max_inputfreq, maxU2 = pll_lim->vco2.max_inputfreq;
+	int minM1 = pll_lim->vco1.min_m, maxM1 = pll_lim->vco1.max_m;
+	int minN1 = pll_lim->vco1.min_n, maxN1 = pll_lim->vco1.max_n;
+	int minM2 = pll_lim->vco2.min_m, maxM2 = pll_lim->vco2.max_m;
+	int minN2 = pll_lim->vco2.min_n, maxN2 = pll_lim->vco2.max_n;
+	int maxlog2P = pll_lim->max_usable_log2p;
+	int crystal = pll_lim->refclk;
+	bool fixedgain2 = (minM2 == maxM2 && minN2 == maxN2);
+	int M1, N1, M2, N2, log2P;
+	int clkP, calcclk1, calcclk2, calcclkout;
+	int delta, bestdelta = INT_MAX;
+	int bestclk = 0;
+
+	int vco2 = (maxvco2 - maxvco2/200) / 2;
+	for (log2P = 0; clk && log2P < maxlog2P && clk <= (vco2 >> log2P); log2P++)
+		;
+	clkP = clk << log2P;
+
+	if (maxvco2 < clk + clk/200)	/* +0.5% */
+		maxvco2 = clk + clk/200;
+
+	for (M1 = minM1; M1 <= maxM1; M1++) {
+		if (crystal/M1 < minU1)
+			return bestclk;
+		if (crystal/M1 > maxU1)
+			continue;
+
+		for (N1 = minN1; N1 <= maxN1; N1++) {
+			calcclk1 = crystal * N1 / M1;
+			if (calcclk1 < minvco1)
+				continue;
+			if (calcclk1 > maxvco1)
+				break;
+
+			for (M2 = minM2; M2 <= maxM2; M2++) {
+				if (calcclk1/M2 < minU2)
+					break;
+				if (calcclk1/M2 > maxU2)
+					continue;
+
+				/* add calcclk1/2 to round better */
+				N2 = (clkP * M2 + calcclk1/2) / calcclk1;
+				if (N2 < minN2)
+					continue;
+				if (N2 > maxN2)
+					break;
+
+				if (!fixedgain2) {
+					if (chip_version < 0x60)
+						if (N2/M2 < 4 || N2/M2 > 10)
+							continue;
+
+					calcclk2 = calcclk1 * N2 / M2;
+					if (calcclk2 < minvco2)
+						break;
+					if (calcclk2 > maxvco2)
+						continue;
+				} else
+					calcclk2 = calcclk1;
+
+				calcclkout = calcclk2 >> log2P;
+				delta = abs(calcclkout - clk);
+				/* we do an exhaustive search rather than terminating
+				 * on an optimality condition...
+				 */
+				if (delta < bestdelta) {
+					bestdelta = delta;
+					bestclk = calcclkout;
+					bestpv->N1 = N1;
+					bestpv->M1 = M1;
+					bestpv->N2 = N2;
+					bestpv->M2 = M2;
+					bestpv->log2P = log2P;
+					if (delta == 0)	/* except this one */
+						return bestclk;
+				}
+			}
+		}
+	}
+
+	return bestclk;
+}
+
+int
+nouveau_calc_pll_mnp(struct drm_device *dev, struct pll_lims *pll_lim, int clk,
+		     struct nouveau_pll_vals *pv)
+{
+	int outclk;
+
+	if (!pll_lim->vco2.maxfreq)
+		outclk = getMNP_single(dev, pll_lim, clk, pv);
+	else
+		outclk = getMNP_double(dev, pll_lim, clk, pv);
+
+	if (!outclk)
+		NV_ERROR(dev, "Could not find a compatible set of PLL values\n");
+
+	return outclk;
+}