xref: /openbmc/linux/drivers/video/fbdev/kyro/STG4000InitDevice.c (revision c900529f3d9161bfde5cca0754f83b4d3c3e0220)
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  
InitSDRAMRegisters(volatile STG4000REG __iomem * pSTGReg,u32 dwSubSysID,u32 dwRevID)83  static u32 InitSDRAMRegisters(volatile STG4000REG __iomem *pSTGReg,
84  			      u32 dwSubSysID, u32 dwRevID)
85  {
86  	static const u8 adwSDRAMArgCfg0[] = { 0xa0, 0x80, 0xa0, 0xa0, 0xa0 };
87  	static const u16 adwSDRAMCfg1[] = { 0x8732, 0x8732, 0xa732, 0xa732, 0x8732 };
88  	static const u16 adwSDRAMCfg2[] = { 0x87d2, 0x87d2, 0xa7d2, 0x87d2, 0xa7d2 };
89  	static const u8 adwSDRAMRsh[] = { 36, 39, 40 };
90  	static const u8 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  
ProgramClock(u32 refClock,u32 coreClock,u32 * FOut,u32 * ROut,u32 * POut)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 ulBestClk = 0, ulBestScore = 0;
124  	u32 ulScore, ulPhaseScore, ulVcoScore;
125  	u32 ulTmp = 0, ulVCO;
126  	u32 ulScaleClockReq, ulMinClock, ulMaxClock;
127  	static const unsigned char 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  							ulBestOD = OD;
193  							ulBestF = F;
194  							ulBestR = R;
195  							ulBestClk = ulTmp;
196  							ulBestScore =
197  							    ulScore;
198  						}
199  						/* is this better, ( aim for highest Score) */
200  			/*--------------------------------------------------------------------------
201                               Here we want to use a scoring system which will take account of both the
202                              value at the phase comparater and the VCO output
203                               to do this we will use a cumulative score between the two
204                            The way this ends up is that we choose the first value in the loop anyway
205                            but we shall keep this code in case new restrictions come into play
206                            --------------------------------------------------------------------------*/
207  						if ((ulScore >= ulBestScore) && (OD > 0)) {
208  							ulBestOD = OD;
209  							ulBestF = F;
210  							ulBestR = R;
211  							ulBestClk = ulTmp;
212  							ulBestScore =
213  							    ulScore;
214  						}
215  					}
216  				}
217  				F++;
218  			}
219  			R++;
220  		}
221  	}
222  
223  	/*
224  	   did we find anything?
225  	   Then return RFOD
226  	 */
227  	if (ulBestScore) {
228  		*ROut = ulBestR;
229  		*FOut = ulBestF;
230  
231  		if ((ulBestOD == 2) || (ulBestOD == 3)) {
232  			*POut = 3;
233  		} else
234  			*POut = ulBestOD;
235  
236  	}
237  
238  	return (ulBestClk);
239  }
240  
SetCoreClockPLL(volatile STG4000REG __iomem * pSTGReg,struct pci_dev * pDev)241  int SetCoreClockPLL(volatile STG4000REG __iomem *pSTGReg, struct pci_dev *pDev)
242  {
243  	u32 F, R, P;
244  	u16 core_pll = 0, sub;
245  	u32 tmp;
246  	u32 ulChipSpeed;
247  
248  	STG_WRITE_REG(IntMask, 0xFFFF);
249  
250  	/* Disable Primary Core Thread0 */
251  	tmp = STG_READ_REG(Thread0Enable);
252  	CLEAR_BIT(0);
253  	STG_WRITE_REG(Thread0Enable, tmp);
254  
255  	/* Disable Primary Core Thread1 */
256  	tmp = STG_READ_REG(Thread1Enable);
257  	CLEAR_BIT(0);
258  	STG_WRITE_REG(Thread1Enable, tmp);
259  
260  	STG_WRITE_REG(SoftwareReset,
261  		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_ROM_RST);
262  	STG_WRITE_REG(SoftwareReset,
263  		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_TA_RST |
264  		      PMX2_SOFTRESET_ROM_RST);
265  
266  	/* Need to play around to reset TA */
267  	STG_WRITE_REG(TAConfiguration, 0);
268  	STG_WRITE_REG(SoftwareReset,
269  		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_ROM_RST);
270  	STG_WRITE_REG(SoftwareReset,
271  		      PMX2_SOFTRESET_REG_RST | PMX2_SOFTRESET_TA_RST |
272  		      PMX2_SOFTRESET_ROM_RST);
273  
274  	pci_read_config_word(pDev, PCI_CONFIG_SUBSYS_ID, &sub);
275  
276  	ulChipSpeed = InitSDRAMRegisters(pSTGReg, (u32)sub,
277  		                         (u32)pDev->revision);
278  
279  	if (ulChipSpeed == 0)
280  		return -EINVAL;
281  
282  	ProgramClock(REF_FREQ, CORE_PLL_FREQ, &F, &R, &P);
283  
284  	core_pll |= ((P) | ((F - 2) << 2) | ((R - 2) << 11));
285  
286  	/* Set Core PLL Control to Core PLL Mode  */
287  
288  	/* Send bits 0:7 of the Core PLL Mode register */
289  	tmp = ((CORE_PLL_MODE_REG_0_7 << 8) | (core_pll & 0x00FF));
290  	pci_write_config_word(pDev, CorePllControl, tmp);
291  	/* Without some delay between the PCI config writes the clock does
292  	   not reliably set when the code is compiled -O3
293  	 */
294  	OS_DELAY(1000000);
295  
296  	tmp |= SET_BIT(14);
297  	pci_write_config_word(pDev, CorePllControl, tmp);
298  	OS_DELAY(1000000);
299  
300  	/* Send bits 8:15 of the Core PLL Mode register */
301  	tmp =
302  	    ((CORE_PLL_MODE_REG_8_15 << 8) | ((core_pll & 0xFF00) >> 8));
303  	pci_write_config_word(pDev, CorePllControl, tmp);
304  	OS_DELAY(1000000);
305  
306  	tmp |= SET_BIT(14);
307  	pci_write_config_word(pDev, CorePllControl, tmp);
308  	OS_DELAY(1000000);
309  
310  	STG_WRITE_REG(SoftwareReset, PMX2_SOFTRESET_ALL);
311  
312  #if 0
313  	/* Enable Primary Core Thread0 */
314  	tmp = ((STG_READ_REG(Thread0Enable)) | SET_BIT(0));
315  	STG_WRITE_REG(Thread0Enable, tmp);
316  
317  	/* Enable Primary Core Thread1 */
318  	tmp = ((STG_READ_REG(Thread1Enable)) | SET_BIT(0));
319  	STG_WRITE_REG(Thread1Enable, tmp);
320  #endif
321  
322  	return 0;
323  }
324