xref: /linux/drivers/video/fbdev/kyro/STG4000InitDevice.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  *  linux/drivers/video/kyro/STG4000InitDevice.c
3  *
4  *  Copyright (C) 2000 Imagination Technologies Ltd
5  *  Copyright (C) 2002 STMicroelectronics
6  *
7  * This file is subject to the terms and conditions of the GNU General Public
8  * License.  See the file COPYING in the main directory of this archive
9  * for more details.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/types.h>
15 #include <linux/pci.h>
16 
17 #include "STG4000Reg.h"
18 #include "STG4000Interface.h"
19 
20 /* SDRAM fixed settings */
21 #define SDRAM_CFG_0   0x49A1
22 #define SDRAM_CFG_1   0xA732
23 #define SDRAM_CFG_2   0x31
24 #define SDRAM_ARB_CFG 0xA0
25 #define SDRAM_REFRESH 0x20
26 
27 /* Reset values */
28 #define PMX2_SOFTRESET_DAC_RST		0x0001
29 #define PMX2_SOFTRESET_C1_RST		0x0004
30 #define PMX2_SOFTRESET_C2_RST		0x0008
31 #define PMX2_SOFTRESET_3D_RST		0x0010
32 #define PMX2_SOFTRESET_VIDIN_RST	0x0020
33 #define PMX2_SOFTRESET_TLB_RST		0x0040
34 #define PMX2_SOFTRESET_SD_RST		0x0080
35 #define PMX2_SOFTRESET_VGA_RST		0x0100
36 #define PMX2_SOFTRESET_ROM_RST		0x0200	/* reserved bit, do not reset */
37 #define PMX2_SOFTRESET_TA_RST		0x0400
38 #define PMX2_SOFTRESET_REG_RST		0x4000
39 #define PMX2_SOFTRESET_ALL		0x7fff
40 
41 /* Core clock freq */
42 #define CORE_PLL_FREQ 1000000
43 
44 /* Reference Clock freq */
45 #define REF_FREQ 14318
46 
47 /* PCI Registers */
48 static u16 CorePllControl = 0x70;
49 
50 #define	PCI_CONFIG_SUBSYS_ID	0x2e
51 
52 /* Misc */
53 #define CORE_PLL_MODE_REG_0_7      3
54 #define CORE_PLL_MODE_REG_8_15     2
55 #define CORE_PLL_MODE_CONFIG_REG   1
56 #define DAC_PLL_CONFIG_REG         0
57 
58 #define STG_MAX_VCO 500000
59 #define STG_MIN_VCO 100000
60 
61 /* PLL Clock */
62 #define    STG4K3_PLL_SCALER      8	/* scale numbers by 2^8 for fixed point calc */
63 #define    STG4K3_PLL_MIN_R       2	/* Minimum multiplier */
64 #define    STG4K3_PLL_MAX_R       33	/* Max */
65 #define    STG4K3_PLL_MIN_F       2	/* Minimum divisor */
66 #define    STG4K3_PLL_MAX_F       513	/* Max */
67 #define    STG4K3_PLL_MIN_OD      0	/* Min output divider (shift) */
68 #define    STG4K3_PLL_MAX_OD      2	/* Max */
69 #define    STG4K3_PLL_MIN_VCO_SC  (100000000 >> STG4K3_PLL_SCALER)	/* Min VCO rate */
70 #define    STG4K3_PLL_MAX_VCO_SC  (500000000 >> STG4K3_PLL_SCALER)	/* Max VCO rate */
71 #define    STG4K3_PLL_MINR_VCO_SC (100000000 >> STG4K3_PLL_SCALER)	/* Min VCO rate (restricted) */
72 #define    STG4K3_PLL_MAXR_VCO_SC (500000000 >> STG4K3_PLL_SCALER)	/* Max VCO rate (restricted) */
73 #define    STG4K3_PLL_MINR_VCO    100000000	/* Min VCO rate (restricted) */
74 #define    STG4K3_PLL_MAX_VCO     500000000	/* Max VCO rate */
75 #define    STG4K3_PLL_MAXR_VCO    500000000	/* Max VCO rate (restricted) */
76 
77 #define OS_DELAY(X) \
78 { \
79 volatile u32 i,count=0; \
80     for(i=0;i<X;i++) count++; \
81 }
82 
83 static u32 InitSDRAMRegisters(volatile STG4000REG __iomem *pSTGReg,
84 			      u32 dwSubSysID, u32 dwRevID)
85 {
86 	u32 adwSDRAMArgCfg0[] = { 0xa0, 0x80, 0xa0, 0xa0, 0xa0 };
87 	u32 adwSDRAMCfg1[] = { 0x8732, 0x8732, 0xa732, 0xa732, 0x8732 };
88 	u32 adwSDRAMCfg2[] = { 0x87d2, 0x87d2, 0xa7d2, 0x87d2, 0xa7d2 };
89 	u32 adwSDRAMRsh[] = { 36, 39, 40 };
90 	u32 adwChipSpeed[] = { 110, 120, 125 };
91 	u32 dwMemTypeIdx;
92 	u32 dwChipSpeedIdx;
93 
94 	/* Get memory tpye and chip speed indexs from the SubSysDevID */
95 	dwMemTypeIdx = (dwSubSysID & 0x70) >> 4;
96 	dwChipSpeedIdx = (dwSubSysID & 0x180) >> 7;
97 
98 	if (dwMemTypeIdx > 4 || dwChipSpeedIdx > 2)
99 		return 0;
100 
101 	/* Program SD-RAM interface */
102 	STG_WRITE_REG(SDRAMArbiterConf, adwSDRAMArgCfg0[dwMemTypeIdx]);
103 	if (dwRevID < 5) {
104 		STG_WRITE_REG(SDRAMConf0, 0x49A1);
105 		STG_WRITE_REG(SDRAMConf1, adwSDRAMCfg1[dwMemTypeIdx]);
106 	} else {
107 		STG_WRITE_REG(SDRAMConf0, 0x4DF1);
108 		STG_WRITE_REG(SDRAMConf1, adwSDRAMCfg2[dwMemTypeIdx]);
109 	}
110 
111 	STG_WRITE_REG(SDRAMConf2, 0x31);
112 	STG_WRITE_REG(SDRAMRefresh, adwSDRAMRsh[dwChipSpeedIdx]);
113 
114 	return adwChipSpeed[dwChipSpeedIdx] * 10000;
115 }
116 
117 u32 ProgramClock(u32 refClock,
118 		   u32 coreClock,
119 		   u32 * FOut, u32 * ROut, u32 * POut)
120 {
121 	u32 R = 0, F = 0, OD = 0, ODIndex = 0;
122 	u32 ulBestR = 0, ulBestF = 0, ulBestOD = 0;
123 	u32 ulBestVCO = 0, ulBestClk = 0, ulBestScore = 0;
124 	u32 ulScore, ulPhaseScore, ulVcoScore;
125 	u32 ulTmp = 0, ulVCO;
126 	u32 ulScaleClockReq, ulMinClock, ulMaxClock;
127 	u32 ODValues[] = { 1, 2, 0 };
128 
129 	/* Translate clock in Hz */
130 	coreClock *= 100;	/* in Hz */
131 	refClock *= 1000;	/* in Hz */
132 
133 	/* Work out acceptable clock
134 	 * The method calculates ~ +- 0.4% (1/256)
135 	 */
136 	ulMinClock = coreClock - (coreClock >> 8);
137 	ulMaxClock = coreClock + (coreClock >> 8);
138 
139 	/* Scale clock required for use in calculations */
140 	ulScaleClockReq = coreClock >> STG4K3_PLL_SCALER;
141 
142 	/* Iterate through post divider values */
143 	for (ODIndex = 0; ODIndex < 3; ODIndex++) {
144 		OD = ODValues[ODIndex];
145 		R = STG4K3_PLL_MIN_R;
146 
147 		/* loop for pre-divider from min to max  */
148 		while (R <= STG4K3_PLL_MAX_R) {
149 			/* estimate required feedback multiplier */
150 			ulTmp = R * (ulScaleClockReq << OD);
151 
152 			/* F = ClkRequired * R * (2^OD) / Fref */
153 			F = (u32)(ulTmp / (refClock >> STG4K3_PLL_SCALER));
154 
155 			/* compensate for accuracy */
156 			if (F > STG4K3_PLL_MIN_F)
157 				F--;
158 
159 
160 			/*
161 			 * We should be close to our target frequency (if it's
162 			 * achievable with current OD & R) let's iterate
163 			 * through F for best fit
164 			 */
165 			while ((F >= STG4K3_PLL_MIN_F) &&
166 			       (F <= STG4K3_PLL_MAX_F)) {
167 				/* Calc VCO at full accuracy */
168 				ulVCO = refClock / R;
169 				ulVCO = F * ulVCO;
170 
171 				/*
172 				 * Check it's within restricted VCO range
173 				 * unless of course the desired frequency is
174 				 * above the restricted range, then test
175 				 * against VCO limit
176 				 */
177 				if ((ulVCO >= STG4K3_PLL_MINR_VCO) &&
178 				    ((ulVCO <= STG4K3_PLL_MAXR_VCO) ||
179 				     ((coreClock > STG4K3_PLL_MAXR_VCO)
180 				      && (ulVCO <= STG4K3_PLL_MAX_VCO)))) {
181 					ulTmp = (ulVCO >> OD);	/* Clock = VCO / (2^OD) */
182 
183 					/* Is this clock good enough? */
184 					if ((ulTmp >= ulMinClock)
185 					    && (ulTmp <= ulMaxClock)) {
186 						ulPhaseScore = (((refClock / R) - (refClock / STG4K3_PLL_MAX_R))) / ((refClock - (refClock / STG4K3_PLL_MAX_R)) >> 10);
187 
188 						ulVcoScore = ((ulVCO - STG4K3_PLL_MINR_VCO)) / ((STG4K3_PLL_MAXR_VCO - STG4K3_PLL_MINR_VCO) >> 10);
189 						ulScore = ulPhaseScore + ulVcoScore;
190 
191 						if (!ulBestScore) {
192 							ulBestVCO = ulVCO;
193 							ulBestOD = OD;
194 							ulBestF = F;
195 							ulBestR = R;
196 							ulBestClk = ulTmp;
197 							ulBestScore =
198 							    ulScore;
199 						}
200 						/* is this better, ( aim for highest Score) */
201 			/*--------------------------------------------------------------------------
202                              Here we want to use a scoring system which will take account of both the
203                             value at the phase comparater and the VCO output
204                              to do this we will use a cumulative score between the two
205                           The way this ends up is that we choose the first value in the loop anyway
206                           but we shall keep this code in case new restrictions come into play
207                           --------------------------------------------------------------------------*/
208 						if ((ulScore >= ulBestScore) && (OD > 0)) {
209 							ulBestVCO = ulVCO;
210 							ulBestOD = OD;
211 							ulBestF = F;
212 							ulBestR = R;
213 							ulBestClk = ulTmp;
214 							ulBestScore =
215 							    ulScore;
216 						}
217 					}
218 				}
219 				F++;
220 			}
221 			R++;
222 		}
223 	}
224 
225 	/*
226 	   did we find anything?
227 	   Then return RFOD
228 	 */
229 	if (ulBestScore) {
230 		*ROut = ulBestR;
231 		*FOut = ulBestF;
232 
233 		if ((ulBestOD == 2) || (ulBestOD == 3)) {
234 			*POut = 3;
235 		} else
236 			*POut = ulBestOD;
237 
238 	}
239 
240 	return (ulBestClk);
241 }
242 
243 int SetCoreClockPLL(volatile STG4000REG __iomem *pSTGReg, struct pci_dev *pDev)
244 {
245 	u32 F, R, P;
246 	u16 core_pll = 0, sub;
247 	u32 ulCoreClock;
248 	u32 tmp;
249 	u32 ulChipSpeed;
250 
251 	STG_WRITE_REG(IntMask, 0xFFFF);
252 
253 	/* Disable Primary Core Thread0 */
254 	tmp = STG_READ_REG(Thread0Enable);
255 	CLEAR_BIT(0);
256 	STG_WRITE_REG(Thread0Enable, tmp);
257 
258 	/* Disable Primary Core Thread1 */
259 	tmp = STG_READ_REG(Thread1Enable);
260 	CLEAR_BIT(0);
261 	STG_WRITE_REG(Thread1Enable, tmp);
262 
263 	STG_WRITE_REG(SoftwareReset,
264 		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_ROM_RST);
265 	STG_WRITE_REG(SoftwareReset,
266 		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_TA_RST |
267 		      PMX2_SOFTRESET_ROM_RST);
268 
269 	/* Need to play around to reset TA */
270 	STG_WRITE_REG(TAConfiguration, 0);
271 	STG_WRITE_REG(SoftwareReset,
272 		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_ROM_RST);
273 	STG_WRITE_REG(SoftwareReset,
274 		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_TA_RST |
275 		      PMX2_SOFTRESET_ROM_RST);
276 
277 	pci_read_config_word(pDev, PCI_CONFIG_SUBSYS_ID, &sub);
278 
279 	ulChipSpeed = InitSDRAMRegisters(pSTGReg, (u32)sub,
280 		                         (u32)pDev->revision);
281 
282 	if (ulChipSpeed == 0)
283 		return -EINVAL;
284 
285 	ulCoreClock = ProgramClock(REF_FREQ, CORE_PLL_FREQ, &F, &R, &P);
286 
287 	core_pll |= ((P) | ((F - 2) << 2) | ((R - 2) << 11));
288 
289 	/* Set Core PLL Control to Core PLL Mode  */
290 
291 	/* Send bits 0:7 of the Core PLL Mode register */
292 	tmp = ((CORE_PLL_MODE_REG_0_7 << 8) | (core_pll & 0x00FF));
293 	pci_write_config_word(pDev, CorePllControl, tmp);
294 	/* Without some delay between the PCI config writes the clock does
295 	   not reliably set when the code is compiled -O3
296 	 */
297 	OS_DELAY(1000000);
298 
299 	tmp |= SET_BIT(14);
300 	pci_write_config_word(pDev, CorePllControl, tmp);
301 	OS_DELAY(1000000);
302 
303 	/* Send bits 8:15 of the Core PLL Mode register */
304 	tmp =
305 	    ((CORE_PLL_MODE_REG_8_15 << 8) | ((core_pll & 0xFF00) >> 8));
306 	pci_write_config_word(pDev, CorePllControl, tmp);
307 	OS_DELAY(1000000);
308 
309 	tmp |= SET_BIT(14);
310 	pci_write_config_word(pDev, CorePllControl, tmp);
311 	OS_DELAY(1000000);
312 
313 	STG_WRITE_REG(SoftwareReset, PMX2_SOFTRESET_ALL);
314 
315 #if 0
316 	/* Enable Primary Core Thread0 */
317 	tmp = ((STG_READ_REG(Thread0Enable)) | SET_BIT(0));
318 	STG_WRITE_REG(Thread0Enable, tmp);
319 
320 	/* Enable Primary Core Thread1 */
321 	tmp = ((STG_READ_REG(Thread1Enable)) | SET_BIT(0));
322 	STG_WRITE_REG(Thread1Enable, tmp);
323 #endif
324 
325 	return 0;
326 }
327