u-boot-brain/board/freescale/p1022ds/diu.c
Timur Tabi 55b05237b9 p1022ds: use weak CFI flash accessors when DIU is enabled
On the Freescale P1022, the DIU and the LBC share address pins, which means
that when the DIU is active (e.g. the console is on the DVI display), NOR flash
cannot be accessed.  So we use the weak accessor function feature of the CFI
flash code to temporarily switch the pin mux from DIU to LBC whenever we want
to read or write flash.  This has a significant performance penalty, but it's
the only way to make it work.

This change allows the 'saveenv' command to work when the video display is
enabled.  Erasing flash and writing to flash (with the 'cp' command) works,
but reading from flash (with the 'md' and 'cp' commands) does not.  Also, while
flash is being written, the video display will be blank.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
2010-09-25 14:42:11 +02:00

305 lines
7.7 KiB
C

/*
* Copyright 2010 Freescale Semiconductor, Inc.
* Authors: Timur Tabi <timur@freescale.com>
*
* FSL DIU Framebuffer driver
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*/
#include <common.h>
#include <command.h>
#include <asm/io.h>
#include <stdio_dev.h>
#include <video_fb.h>
#include "../common/ngpixis.h"
#include <fsl_diu_fb.h>
/* The CTL register is called 'csr' in the ngpixis_t structure */
#define PX_CTL_ALTACC 0x80
#define PX_BRDCFG0_ELBC_SPI_MASK 0xc0
#define PX_BRDCFG0_ELBC_SPI_ELBC 0x00
#define PX_BRDCFG0_ELBC_SPI_NULL 0xc0
#define PX_BRDCFG0_ELBC_DIU 0x02
#define PX_BRDCFG1_DVIEN 0x80
#define PX_BRDCFG1_DFPEN 0x40
#define PX_BRDCFG1_BACKLIGHT 0x20
#define PMUXCR_ELBCDIU_MASK 0xc0000000
#define PMUXCR_ELBCDIU_NOR16 0x80000000
/*
* DIU Area Descriptor
*
* Note that we need to byte-swap the value before it's written to the AD
* register. So even though the registers don't look like they're in the same
* bit positions as they are on the MPC8610, the same value is written to the
* AD register on the MPC8610 and on the P1022.
*/
#define AD_BYTE_F 0x10000000
#define AD_ALPHA_C_SHIFT 25
#define AD_BLUE_C_SHIFT 23
#define AD_GREEN_C_SHIFT 21
#define AD_RED_C_SHIFT 19
#define AD_PIXEL_S_SHIFT 16
#define AD_COMP_3_SHIFT 12
#define AD_COMP_2_SHIFT 8
#define AD_COMP_1_SHIFT 4
#define AD_COMP_0_SHIFT 0
/*
* Variables used by the DIU/LBC switching code. It's safe to makes these
* global, because the DIU requires DDR, so we'll only run this code after
* relocation.
*/
static u8 px_brdcfg0;
static u32 pmuxcr;
static void *lbc_lcs0_ba;
static void *lbc_lcs1_ba;
void diu_set_pixel_clock(unsigned int pixclock)
{
ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
unsigned long speed_ccb, temp;
u32 pixval;
speed_ccb = get_bus_freq(0);
temp = 1000000000 / pixclock;
temp *= 1000;
pixval = speed_ccb / temp;
debug("DIU pixval = %lu\n", pixval);
/* Modify PXCLK in GUTS CLKDVDR */
temp = in_be32(&gur->clkdvdr) & 0x2000FFFF;
out_be32(&gur->clkdvdr, temp); /* turn off clock */
out_be32(&gur->clkdvdr, temp | 0x80000000 | ((pixval & 0x1F) << 16));
}
int platform_diu_init(unsigned int *xres, unsigned int *yres)
{
ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
char *monitor_port;
u32 pixel_format;
u8 temp;
/* Save the LBC LCS0 and LCS1 addresses for the DIU mux functions */
lbc_lcs0_ba = (void *)(get_lbc_br(0) & get_lbc_or(0) & 0xFFFF8000);
lbc_lcs1_ba = (void *)(get_lbc_br(1) & get_lbc_or(1) & 0xFFFF8000);
pixel_format = cpu_to_le32(AD_BYTE_F | (3 << AD_ALPHA_C_SHIFT) |
(0 << AD_BLUE_C_SHIFT) | (1 << AD_GREEN_C_SHIFT) |
(2 << AD_RED_C_SHIFT) | (8 << AD_COMP_3_SHIFT) |
(8 << AD_COMP_2_SHIFT) | (8 << AD_COMP_1_SHIFT) |
(8 << AD_COMP_0_SHIFT) | (3 << AD_PIXEL_S_SHIFT));
temp = in_8(&pixis->brdcfg1);
monitor_port = getenv("monitor");
if (!strncmp(monitor_port, "1", 1)) { /* 1 - Single link LVDS */
*xres = 1024;
*yres = 768;
/* Enable the DFP port, disable the DVI and the backlight */
temp &= ~(PX_BRDCFG1_DVIEN | PX_BRDCFG1_BACKLIGHT);
temp |= PX_BRDCFG1_DFPEN;
} else { /* DVI */
*xres = 1280;
*yres = 1024;
/* Enable the DVI port, disable the DFP and the backlight */
temp &= ~(PX_BRDCFG1_DFPEN | PX_BRDCFG1_BACKLIGHT);
temp |= PX_BRDCFG1_DVIEN;
}
out_8(&pixis->brdcfg1, temp);
/*
* Enable PIXIS indirect access mode. This is a hack that allows us to
* access PIXIS registers even when the LBC pins have been muxed to the
* DIU.
*/
setbits_8(&pixis->csr, PX_CTL_ALTACC);
/*
* Route the LAD pins to the DIU. This will disable access to the eLBC,
* which means we won't be able to read/write any NOR flash addresses!
*/
out_8(lbc_lcs0_ba, offsetof(ngpixis_t, brdcfg0));
px_brdcfg0 = in_8(lbc_lcs1_ba);
out_8(lbc_lcs1_ba, px_brdcfg0 | PX_BRDCFG0_ELBC_DIU);
/* Setting PMUXCR to switch to DVI from ELBC */
clrsetbits_be32(&gur->pmuxcr,
PMUXCR_ELBCDIU_MASK, PMUXCR_ELBCDIU_NOR16);
pmuxcr = in_be32(&gur->pmuxcr);
return fsl_diu_init(*xres, pixel_format, 0);
}
#ifdef CONFIG_CFI_FLASH_USE_WEAK_ACCESSORS
/*
* set_mux_to_lbc - disable the DIU so that we can read/write to elbc
*
* On the Freescale P1022, the DIU video signal and the LBC address/data lines
* share the same pins, which means that when the DIU is active (e.g. the
* console is on the DVI display), NOR flash cannot be accessed. So we use the
* weak accessor feature of the CFI flash code to temporarily switch the pin
* mux from DIU to LBC whenever we want to read or write flash. This has a
* significant performance penalty, but it's the only way to make it work.
*
* There are two muxes: one on the chip, and one on the board. The chip mux
* controls whether the pins are used for the DIU or the LBC, and it is
* set via PMUXCR. The board mux controls whether those signals go to
* the video connector or the NOR flash chips, and it is set via the ngPIXIS.
*/
static int set_mux_to_lbc(void)
{
ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
/* Switch the muxes only if they're currently set to DIU mode */
if ((in_be32(&gur->pmuxcr) & PMUXCR_ELBCDIU_MASK) ==
PMUXCR_ELBCDIU_NOR16) {
/*
* In DIU mode, the PIXIS can only be accessed indirectly
* since we can't read/write the LBC directly.
*/
/* Set the board mux to LBC. This will disable the display. */
out_8(lbc_lcs0_ba, offsetof(ngpixis_t, brdcfg0));
px_brdcfg0 = in_8(lbc_lcs1_ba);
out_8(lbc_lcs1_ba, (px_brdcfg0 & ~(PX_BRDCFG0_ELBC_SPI_MASK
| PX_BRDCFG0_ELBC_DIU)) | PX_BRDCFG0_ELBC_SPI_ELBC);
/* Disable indirect PIXIS mode */
out_8(lbc_lcs0_ba, offsetof(ngpixis_t, csr));
clrbits_8(lbc_lcs1_ba, PX_CTL_ALTACC);
/* Set the chip mux to LBC mode, so that writes go to flash. */
out_be32(&gur->pmuxcr, (pmuxcr & ~PMUXCR_ELBCDIU_MASK) |
PMUXCR_ELBCDIU_NOR16);
in_be32(&gur->pmuxcr);
return 1;
}
return 0;
}
/*
* set_mux_to_diu - re-enable the DIU muxing
*
* This function restores the chip and board muxing to point to the DIU.
*/
static void set_mux_to_diu(void)
{
ccsr_gur_t *gur = (void *)CONFIG_SYS_MPC85xx_GUTS_ADDR;
/* Enable indirect PIXIS mode */
setbits_8(&pixis->csr, PX_CTL_ALTACC);
/* Set the board mux to DIU. This will enable the display. */
out_8(lbc_lcs0_ba, offsetof(ngpixis_t, brdcfg0));
out_8(lbc_lcs1_ba, px_brdcfg0);
in_8(lbc_lcs1_ba);
/* Set the chip mux to DIU mode. */
out_be32(&gur->pmuxcr, pmuxcr);
in_be32(&gur->pmuxcr);
}
void flash_write8(u8 value, void *addr)
{
int sw = set_mux_to_lbc();
__raw_writeb(value, addr);
if (sw)
set_mux_to_diu();
}
void flash_write16(u16 value, void *addr)
{
int sw = set_mux_to_lbc();
__raw_writew(value, addr);
if (sw)
set_mux_to_diu();
}
void flash_write32(u32 value, void *addr)
{
int sw = set_mux_to_lbc();
__raw_writel(value, addr);
if (sw)
set_mux_to_diu();
}
void flash_write64(u64 value, void *addr)
{
int sw = set_mux_to_lbc();
/* There is no __raw_writeq(), so do the write manually */
*(volatile u64 *)addr = value;
if (sw)
set_mux_to_diu();
}
u8 flash_read8(void *addr)
{
u8 ret;
int sw = set_mux_to_lbc();
ret = __raw_readb(addr);
if (sw)
set_mux_to_diu();
return ret;
}
u16 flash_read16(void *addr)
{
u16 ret;
int sw = set_mux_to_lbc();
ret = __raw_readw(addr);
if (sw)
set_mux_to_diu();
return ret;
}
u32 flash_read32(void *addr)
{
u32 ret;
int sw = set_mux_to_lbc();
ret = __raw_readl(addr);
if (sw)
set_mux_to_diu();
return ret;
}
u64 flash_read64(void *addr)
{
u64 ret;
int sw = set_mux_to_lbc();
/* There is no __raw_readq(), so do the read manually */
ret = *(volatile u64 *)addr;
if (sw)
set_mux_to_diu();
return ret;
}
#endif