xref: /openbmc/u-boot/board/freescale/p1022ds/diu.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2010-2011 Freescale Semiconductor, Inc.
4  * Authors: Timur Tabi <timur@freescale.com>
5  *
6  * FSL DIU Framebuffer driver
7  */
8 
9 #include <common.h>
10 #include <command.h>
11 #include <linux/ctype.h>
12 #include <asm/io.h>
13 #include <stdio_dev.h>
14 #include <video_fb.h>
15 #include "../common/ngpixis.h"
16 #include <fsl_diu_fb.h>
17 
18 /* The CTL register is called 'csr' in the ngpixis_t structure */
19 #define PX_CTL_ALTACC		0x80
20 
21 #define PX_BRDCFG0_ELBC_SPI_MASK	0xc0
22 #define PX_BRDCFG0_ELBC_SPI_ELBC	0x00
23 #define PX_BRDCFG0_ELBC_SPI_NULL	0xc0
24 #define PX_BRDCFG0_ELBC_DIU		0x02
25 
26 #define PX_BRDCFG1_DVIEN	0x80
27 #define PX_BRDCFG1_DFPEN	0x40
28 #define PX_BRDCFG1_BACKLIGHT	0x20
29 
30 #define PMUXCR_ELBCDIU_MASK	0xc0000000
31 #define PMUXCR_ELBCDIU_NOR16	0x80000000
32 #define PMUXCR_ELBCDIU_DIU	0x40000000
33 
34 /*
35  * DIU Area Descriptor
36  *
37  * Note that we need to byte-swap the value before it's written to the AD
38  * register.  So even though the registers don't look like they're in the same
39  * bit positions as they are on the MPC8610, the same value is written to the
40  * AD register on the MPC8610 and on the P1022.
41  */
42 #define AD_BYTE_F		0x10000000
43 #define AD_ALPHA_C_SHIFT	25
44 #define AD_BLUE_C_SHIFT		23
45 #define AD_GREEN_C_SHIFT	21
46 #define AD_RED_C_SHIFT		19
47 #define AD_PIXEL_S_SHIFT	16
48 #define AD_COMP_3_SHIFT		12
49 #define AD_COMP_2_SHIFT		8
50 #define AD_COMP_1_SHIFT		4
51 #define AD_COMP_0_SHIFT		0
52 
53 /*
54  * Variables used by the DIU/LBC switching code.  It's safe to makes these
55  * global, because the DIU requires DDR, so we'll only run this code after
56  * relocation.
57  */
58 static u8 px_brdcfg0;
59 static u32 pmuxcr;
60 static void *lbc_lcs0_ba;
61 static void *lbc_lcs1_ba;
62 static u32 old_br0, old_or0, old_br1, old_or1;
63 static u32 new_br0, new_or0, new_br1, new_or1;
64 
65 void diu_set_pixel_clock(unsigned int pixclock)
66 {
67 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
68 	unsigned long speed_ccb, temp;
69 	u32 pixval;
70 
71 	speed_ccb = get_bus_freq(0);
72 	temp = 1000000000 / pixclock;
73 	temp *= 1000;
74 	pixval = speed_ccb / temp;
75 	debug("DIU pixval = %u\n", pixval);
76 
77 	/* Modify PXCLK in GUTS CLKDVDR */
78 	temp = in_be32(&gur->clkdvdr) & 0x2000FFFF;
79 	out_be32(&gur->clkdvdr, temp);			/* turn off clock */
80 	out_be32(&gur->clkdvdr, temp | 0x80000000 | ((pixval & 0x1F) << 16));
81 }
82 
83 int platform_diu_init(unsigned int xres, unsigned int yres, const char *port)
84 {
85 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
86 	const char *name;
87 	u32 pixel_format;
88 	u8 temp;
89 	phys_addr_t phys0, phys1; /* BR0/BR1 physical addresses */
90 
91 	/*
92 	 * Indirect mode requires both BR0 and BR1 to be set to "GPCM",
93 	 * otherwise writes to these addresses won't actually appear on the
94 	 * local bus, and so the PIXIS won't see them.
95 	 *
96 	 * In FCM mode, writes go to the NAND controller, which does not pass
97 	 * them to the localbus directly.  So we force BR0 and BR1 into GPCM
98 	 * mode, since we don't care about what's behind the localbus any
99 	 * more.  However, we save those registers first, so that we can
100 	 * restore them when necessary.
101 	 */
102 	new_br0 = old_br0 = get_lbc_br(0);
103 	new_br1 = old_br1 = get_lbc_br(1);
104 	new_or0 = old_or0 = get_lbc_or(0);
105 	new_or1 = old_or1 = get_lbc_or(1);
106 
107 	/*
108 	 * Use the existing BRx/ORx values if it's already GPCM. Otherwise,
109 	 * force the values to simple 32KB GPCM windows with the most
110 	 * conservative timing.
111 	 */
112 	if ((old_br0 & BR_MSEL) != BR_MS_GPCM) {
113 		new_br0 = (get_lbc_br(0) & BR_BA) | BR_V;
114 		new_or0 = OR_AM_32KB | 0xFF7;
115 		set_lbc_br(0, new_br0);
116 		set_lbc_or(0, new_or0);
117 	}
118 	if ((old_br1 & BR_MSEL) != BR_MS_GPCM) {
119 		new_br1 = (get_lbc_br(1) & BR_BA) | BR_V;
120 		new_or1 = OR_AM_32KB | 0xFF7;
121 		set_lbc_br(1, new_br1);
122 		set_lbc_or(1, new_or1);
123 	}
124 
125 	/*
126 	 * Determine the physical addresses for Chip Selects 0 and 1.  The
127 	 * BR0/BR1 registers contain the truncated physical addresses for the
128 	 * chip selects, mapped via the localbus LAW.  Since the BRx registers
129 	 * only contain the lower 32 bits of the address, we have to determine
130 	 * the upper 4 bits some other way.  The proper way is to scan the LAW
131 	 * table looking for a matching localbus address. Instead, we cheat.
132 	 * We know that the upper bits are 0 for 32-bit addressing, or 0xF for
133 	 * 36-bit addressing.
134 	 */
135 #ifdef CONFIG_PHYS_64BIT
136 	phys0 = 0xf00000000ULL | (old_br0 & old_or0 & BR_BA);
137 	phys1 = 0xf00000000ULL | (old_br1 & old_or1 & BR_BA);
138 #else
139 	phys0 = old_br0 & old_or0 & BR_BA;
140 	phys1 = old_br1 & old_or1 & BR_BA;
141 #endif
142 
143 	 /* Save the LBC LCS0 and LCS1 addresses for the DIU mux functions */
144 	lbc_lcs0_ba = map_physmem(phys0, 1, 0);
145 	lbc_lcs1_ba = map_physmem(phys1, 1, 0);
146 
147 	pixel_format = cpu_to_le32(AD_BYTE_F | (3 << AD_ALPHA_C_SHIFT) |
148 		(0 << AD_BLUE_C_SHIFT) | (1 << AD_GREEN_C_SHIFT) |
149 		(2 << AD_RED_C_SHIFT) | (8 << AD_COMP_3_SHIFT) |
150 		(8 << AD_COMP_2_SHIFT) | (8 << AD_COMP_1_SHIFT) |
151 		(8 << AD_COMP_0_SHIFT) | (3 << AD_PIXEL_S_SHIFT));
152 
153 	temp = in_8(&pixis->brdcfg1);
154 
155 	if (strncmp(port, "lvds", 4) == 0) {
156 		/* Single link LVDS */
157 		temp &= ~PX_BRDCFG1_DVIEN;
158 		/*
159 		 * LVDS also needs backlight enabled, otherwise the display
160 		 * will be blank.
161 		 */
162 		temp |= (PX_BRDCFG1_DFPEN | PX_BRDCFG1_BACKLIGHT);
163 		name = "Single-Link LVDS";
164 	} else {	/* DVI */
165 		/* Enable the DVI port, disable the DFP and the backlight */
166 		temp &= ~(PX_BRDCFG1_DFPEN | PX_BRDCFG1_BACKLIGHT);
167 		temp |= PX_BRDCFG1_DVIEN;
168 		name = "DVI";
169 	}
170 
171 	printf("DIU:   Switching to %s monitor @ %ux%u\n", name, xres, yres);
172 	out_8(&pixis->brdcfg1, temp);
173 
174 	/*
175 	 * Enable PIXIS indirect access mode.  This is a hack that allows us to
176 	 * access PIXIS registers even when the LBC pins have been muxed to the
177 	 * DIU.
178 	 */
179 	setbits_8(&pixis->csr, PX_CTL_ALTACC);
180 
181 	/*
182 	 * Route the LAD pins to the DIU.  This will disable access to the eLBC,
183 	 * which means we won't be able to read/write any NOR flash addresses!
184 	 */
185 	out_8(lbc_lcs0_ba, offsetof(ngpixis_t, brdcfg0));
186 	px_brdcfg0 = in_8(lbc_lcs1_ba);
187 	out_8(lbc_lcs1_ba, px_brdcfg0 | PX_BRDCFG0_ELBC_DIU);
188 	in_8(lbc_lcs1_ba);
189 
190 	/* Set PMUXCR to switch the muxed pins from the LBC to the DIU */
191 	clrsetbits_be32(&gur->pmuxcr, PMUXCR_ELBCDIU_MASK, PMUXCR_ELBCDIU_DIU);
192 	pmuxcr = in_be32(&gur->pmuxcr);
193 
194 	return fsl_diu_init(xres, yres, pixel_format, 0);
195 }
196 
197 /*
198  * set_mux_to_lbc - disable the DIU so that we can read/write to elbc
199  *
200  * On the Freescale P1022, the DIU video signal and the LBC address/data lines
201  * share the same pins, which means that when the DIU is active (e.g. the
202  * console is on the DVI display), NOR flash cannot be accessed.  So we use the
203  * weak accessor feature of the CFI flash code to temporarily switch the pin
204  * mux from DIU to LBC whenever we want to read or write flash.  This has a
205  * significant performance penalty, but it's the only way to make it work.
206  *
207  * There are two muxes: one on the chip, and one on the board. The chip mux
208  * controls whether the pins are used for the DIU or the LBC, and it is
209  * set via PMUXCR.  The board mux controls whether those signals go to
210  * the video connector or the NOR flash chips, and it is set via the ngPIXIS.
211  */
212 static int set_mux_to_lbc(void)
213 {
214 	ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
215 
216 	/* Switch the muxes only if they're currently set to DIU mode */
217 	if ((in_be32(&gur->pmuxcr) & PMUXCR_ELBCDIU_MASK) !=
218 	    PMUXCR_ELBCDIU_NOR16) {
219 		/*
220 		 * In DIU mode, the PIXIS can only be accessed indirectly
221 		 * since we can't read/write the LBC directly.
222 		 */
223 		/* Set the board mux to LBC.  This will disable the display. */
224 		out_8(lbc_lcs0_ba, offsetof(ngpixis_t, brdcfg0));
225 		out_8(lbc_lcs1_ba, px_brdcfg0);
226 		in_8(lbc_lcs1_ba);
227 
228 		/* Disable indirect PIXIS mode */
229 		out_8(lbc_lcs0_ba, offsetof(ngpixis_t, csr));
230 		clrbits_8(lbc_lcs1_ba, PX_CTL_ALTACC);
231 
232 		/* Set the chip mux to LBC mode, so that writes go to flash. */
233 		out_be32(&gur->pmuxcr, (pmuxcr & ~PMUXCR_ELBCDIU_MASK) |
234 			 PMUXCR_ELBCDIU_NOR16);
235 		in_be32(&gur->pmuxcr);
236 
237 		/* Restore the BR0 and BR1 settings */
238 		set_lbc_br(0, old_br0);
239 		set_lbc_or(0, old_or0);
240 		set_lbc_br(1, old_br1);
241 		set_lbc_or(1, old_or1);
242 
243 		return 1;
244 	}
245 
246 	return 0;
247 }
248 
249 /*
250  * set_mux_to_diu - re-enable the DIU muxing
251  *
252  * This function restores the chip and board muxing to point to the DIU.
253  */
254 static void set_mux_to_diu(void)
255 {
256 	ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
257 
258 	/* Set BR0 and BR1 to GPCM mode */
259 	set_lbc_br(0, new_br0);
260 	set_lbc_or(0, new_or0);
261 	set_lbc_br(1, new_br1);
262 	set_lbc_or(1, new_or1);
263 
264 	/* Enable indirect PIXIS mode */
265 	setbits_8(&pixis->csr, PX_CTL_ALTACC);
266 
267 	/* Set the board mux to DIU.  This will enable the display. */
268 	out_8(lbc_lcs0_ba, offsetof(ngpixis_t, brdcfg0));
269 	out_8(lbc_lcs1_ba, px_brdcfg0 | PX_BRDCFG0_ELBC_DIU);
270 	in_8(lbc_lcs1_ba);
271 
272 	/* Set the chip mux to DIU mode. */
273 	out_be32(&gur->pmuxcr, pmuxcr);
274 	in_be32(&gur->pmuxcr);
275 }
276 
277 /*
278  * pixis_read - board-specific function to read from the PIXIS
279  *
280  * This function overrides the generic pixis_read() function, so that it can
281  * use PIXIS indirect mode if necessary.
282  */
283 u8 pixis_read(unsigned int reg)
284 {
285 	ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
286 
287 	/* Use indirect mode if the mux is currently set to DIU mode */
288 	if ((in_be32(&gur->pmuxcr) & PMUXCR_ELBCDIU_MASK) !=
289 	    PMUXCR_ELBCDIU_NOR16) {
290 		out_8(lbc_lcs0_ba, reg);
291 		return in_8(lbc_lcs1_ba);
292 	} else {
293 		void *p = (void *)PIXIS_BASE;
294 
295 		return in_8(p + reg);
296 	}
297 }
298 
299 /*
300  * pixis_write - board-specific function to write to the PIXIS
301  *
302  * This function overrides the generic pixis_write() function, so that it can
303  * use PIXIS indirect mode if necessary.
304  */
305 void pixis_write(unsigned int reg, u8 value)
306 {
307 	ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
308 
309 	/* Use indirect mode if the mux is currently set to DIU mode */
310 	if ((in_be32(&gur->pmuxcr) & PMUXCR_ELBCDIU_MASK) !=
311 	    PMUXCR_ELBCDIU_NOR16) {
312 		out_8(lbc_lcs0_ba, reg);
313 		out_8(lbc_lcs1_ba, value);
314 		/* Do a read-back to ensure the write completed */
315 		in_8(lbc_lcs1_ba);
316 	} else {
317 		void *p = (void *)PIXIS_BASE;
318 
319 		out_8(p + reg, value);
320 	}
321 }
322 
323 void pixis_bank_reset(void)
324 {
325 	/*
326 	 * For some reason, a PIXIS bank reset does not work if the PIXIS is
327 	 * in indirect mode, so switch to direct mode first.
328 	 */
329 	set_mux_to_lbc();
330 
331 	out_8(&pixis->vctl, 0);
332 	out_8(&pixis->vctl, 1);
333 
334 	while (1);
335 }
336 
337 #ifdef CONFIG_CFI_FLASH_USE_WEAK_ACCESSORS
338 
339 void flash_write8(u8 value, void *addr)
340 {
341 	int sw = set_mux_to_lbc();
342 
343 	__raw_writeb(value, addr);
344 	if (sw) {
345 		/*
346 		 * To ensure the post-write is completed to eLBC, software must
347 		 * perform a dummy read from one valid address from eLBC space
348 		 * before changing the eLBC_DIU from NOR mode to DIU mode.
349 		 * set_mux_to_diu() includes a sync that will ensure the
350 		 * __raw_readb() completes before it switches the mux.
351 		 */
352 		__raw_readb(addr);
353 		set_mux_to_diu();
354 	}
355 }
356 
357 void flash_write16(u16 value, void *addr)
358 {
359 	int sw = set_mux_to_lbc();
360 
361 	__raw_writew(value, addr);
362 	if (sw) {
363 		/*
364 		 * To ensure the post-write is completed to eLBC, software must
365 		 * perform a dummy read from one valid address from eLBC space
366 		 * before changing the eLBC_DIU from NOR mode to DIU mode.
367 		 * set_mux_to_diu() includes a sync that will ensure the
368 		 * __raw_readb() completes before it switches the mux.
369 		 */
370 		__raw_readb(addr);
371 		set_mux_to_diu();
372 	}
373 }
374 
375 void flash_write32(u32 value, void *addr)
376 {
377 	int sw = set_mux_to_lbc();
378 
379 	__raw_writel(value, addr);
380 	if (sw) {
381 		/*
382 		 * To ensure the post-write is completed to eLBC, software must
383 		 * perform a dummy read from one valid address from eLBC space
384 		 * before changing the eLBC_DIU from NOR mode to DIU mode.
385 		 * set_mux_to_diu() includes a sync that will ensure the
386 		 * __raw_readb() completes before it switches the mux.
387 		 */
388 		__raw_readb(addr);
389 		set_mux_to_diu();
390 	}
391 }
392 
393 void flash_write64(u64 value, void *addr)
394 {
395 	int sw = set_mux_to_lbc();
396 	uint32_t *p = addr;
397 
398 	/*
399 	 * There is no __raw_writeq(), so do the write manually.  We don't trust
400 	 * the compiler, so we use inline assembly.
401 	 */
402 	__asm__ __volatile__(
403 		"stw%U0%X0 %2,%0;\n"
404 		"stw%U1%X1 %3,%1;\n"
405 		: "=m" (*p), "=m" (*(p + 1))
406 		: "r" ((uint32_t) (value >> 32)), "r" ((uint32_t) (value)));
407 
408 	if (sw) {
409 		/*
410 		 * To ensure the post-write is completed to eLBC, software must
411 		 * perform a dummy read from one valid address from eLBC space
412 		 * before changing the eLBC_DIU from NOR mode to DIU mode.  We
413 		 * read addr+4 because we just wrote to addr+4, so that's how we
414 		 * maintain execution order.  set_mux_to_diu() includes a sync
415 		 * that will ensure the __raw_readb() completes before it
416 		 * switches the mux.
417 		 */
418 		__raw_readb(addr + 4);
419 		set_mux_to_diu();
420 	}
421 }
422 
423 u8 flash_read8(void *addr)
424 {
425 	u8 ret;
426 
427 	int sw = set_mux_to_lbc();
428 
429 	ret = __raw_readb(addr);
430 	if (sw)
431 		set_mux_to_diu();
432 
433 	return ret;
434 }
435 
436 u16 flash_read16(void *addr)
437 {
438 	u16 ret;
439 
440 	int sw = set_mux_to_lbc();
441 
442 	ret = __raw_readw(addr);
443 	if (sw)
444 		set_mux_to_diu();
445 
446 	return ret;
447 }
448 
449 u32 flash_read32(void *addr)
450 {
451 	u32 ret;
452 
453 	int sw = set_mux_to_lbc();
454 
455 	ret = __raw_readl(addr);
456 	if (sw)
457 		set_mux_to_diu();
458 
459 	return ret;
460 }
461 
462 u64 flash_read64(void *addr)
463 {
464 	u64 ret;
465 
466 	int sw = set_mux_to_lbc();
467 
468 	/* There is no __raw_readq(), so do the read manually */
469 	ret = *(volatile u64 *)addr;
470 	if (sw)
471 		set_mux_to_diu();
472 
473 	return ret;
474 }
475 
476 #endif
477