u-boot-brain/drivers/video/am335x-fb.c
Hannes Schmelzer 8a094f508c am335x-fb: setup display PLL
The LCDC IP-core an be feed from several clock sources, one of those is
a dedicated DPLL for generating a dividable base-clock for this IP-core.

The TRM specifies the maximum input frequency for the LCCD with 200 MHz,
so we must not exceed this value with the PLL frequency (which can lock
much higher).

This patch tries every combination of multipliers and divisors of the
PLL and the IP-core itself for getting as near as possible the the
requested panel->pxl_clk.

Signed-off-by: Hannes Schmelzer <oe5hpm@oevsv.at>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
2018-01-11 15:19:12 +01:00

237 lines
7.2 KiB
C

/*
* Copyright (C) 2013-2018 Hannes Schmelzer <oe5hpm@oevsv.at>
* B&R Industrial Automation GmbH - http://www.br-automation.com
*
* minimal framebuffer driver for TI's AM335x SoC to be compatible with
* Wolfgang Denk's LCD-Framework (CONFIG_LCD, common/lcd.c)
*
* - supporting 16/24/32bit RGB/TFT raster Mode (not using palette)
* - sets up LCD controller as in 'am335x_lcdpanel' struct given
* - starts output DMA from gd->fb_base buffer
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/arch/omap.h>
#include <asm/arch/clock.h>
#include <asm/arch/sys_proto.h>
#include <lcd.h>
#include "am335x-fb.h"
#if !defined(LCD_CNTL_BASE)
#error "hw-base address of LCD-Controller (LCD_CNTL_BASE) not defined!"
#endif
#define LCDC_FMAX 200000000
/* LCD Control Register */
#define LCD_CLK_DIVISOR(x) ((x) << 8)
#define LCD_RASTER_MODE 0x01
/* LCD Clock Enable Register */
#define LCD_CORECLKEN (0x01 << 0)
#define LCD_LIDDCLKEN (0x01 << 1)
#define LCD_DMACLKEN (0x01 << 2)
/* LCD DMA Control Register */
#define LCD_DMA_BURST_SIZE(x) ((x) << 4)
#define LCD_DMA_BURST_1 0x0
#define LCD_DMA_BURST_2 0x1
#define LCD_DMA_BURST_4 0x2
#define LCD_DMA_BURST_8 0x3
#define LCD_DMA_BURST_16 0x4
/* LCD Timing_0 Register */
#define LCD_HBPLSB(x) ((((x)-1) & 0xFF) << 24)
#define LCD_HFPLSB(x) ((((x)-1) & 0xFF) << 16)
#define LCD_HSWLSB(x) ((((x)-1) & 0x3F) << 10)
#define LCD_HORLSB(x) (((((x) >> 4)-1) & 0x3F) << 4)
#define LCD_HORMSB(x) (((((x) >> 4)-1) & 0x40) >> 4)
/* LCD Timing_1 Register */
#define LCD_VBP(x) ((x) << 24)
#define LCD_VFP(x) ((x) << 16)
#define LCD_VSW(x) (((x)-1) << 10)
#define LCD_VERLSB(x) (((x)-1) & 0x3FF)
/* LCD Timing_2 Register */
#define LCD_HSWMSB(x) ((((x)-1) & 0x3C0) << 21)
#define LCD_VERMSB(x) ((((x)-1) & 0x400) << 16)
#define LCD_HBPMSB(x) ((((x)-1) & 0x300) >> 4)
#define LCD_HFPMSB(x) ((((x)-1) & 0x300) >> 8)
#define LCD_INVMASK(x) ((x) & 0x3F00000)
/* LCD Raster Ctrl Register */
#define LCD_TFT_24BPP_MODE (1 << 25)
#define LCD_TFT_24BPP_UNPACK (1 << 26)
#define LCD_PALMODE_RAWDATA (0x02 << 20)
#define LCD_TFT_MODE (0x01 << 7)
#define LCD_RASTER_ENABLE (0x01 << 0)
/* Macro definitions */
#define FBSIZE(x) ((x->hactive * x->vactive * x->bpp) >> 3)
struct am335x_lcdhw {
unsigned int pid; /* 0x00 */
unsigned int ctrl; /* 0x04 */
unsigned int gap0; /* 0x08 */
unsigned int lidd_ctrl; /* 0x0C */
unsigned int lidd_cs0_conf; /* 0x10 */
unsigned int lidd_cs0_addr; /* 0x14 */
unsigned int lidd_cs0_data; /* 0x18 */
unsigned int lidd_cs1_conf; /* 0x1C */
unsigned int lidd_cs1_addr; /* 0x20 */
unsigned int lidd_cs1_data; /* 0x24 */
unsigned int raster_ctrl; /* 0x28 */
unsigned int raster_timing0; /* 0x2C */
unsigned int raster_timing1; /* 0x30 */
unsigned int raster_timing2; /* 0x34 */
unsigned int raster_subpanel; /* 0x38 */
unsigned int raster_subpanel2; /* 0x3C */
unsigned int lcddma_ctrl; /* 0x40 */
unsigned int lcddma_fb0_base; /* 0x44 */
unsigned int lcddma_fb0_ceiling; /* 0x48 */
unsigned int lcddma_fb1_base; /* 0x4C */
unsigned int lcddma_fb1_ceiling; /* 0x50 */
unsigned int sysconfig; /* 0x54 */
unsigned int irqstatus_raw; /* 0x58 */
unsigned int irqstatus; /* 0x5C */
unsigned int irqenable_set; /* 0x60 */
unsigned int irqenable_clear; /* 0x64 */
unsigned int gap1; /* 0x68 */
unsigned int clkc_enable; /* 0x6C */
unsigned int clkc_reset; /* 0x70 */
};
static struct am335x_lcdhw *lcdhw = (void *)LCD_CNTL_BASE;
DECLARE_GLOBAL_DATA_PTR;
int lcd_get_size(int *line_length)
{
*line_length = (panel_info.vl_col * NBITS(panel_info.vl_bpix)) / 8;
return *line_length * panel_info.vl_row + 0x20;
}
int am335xfb_init(struct am335x_lcdpanel *panel)
{
u32 raster_ctrl = 0;
struct cm_dpll *const cmdpll = (struct cm_dpll *)CM_DPLL;
struct dpll_params dpll_disp = { 1, 0, 1, -1, -1, -1, -1 };
unsigned int m, n, d, best_d = 2;
int err = 0, err_r = 0;
if (gd->fb_base == 0) {
printf("ERROR: no valid fb_base stored in GLOBAL_DATA_PTR!\n");
return -1;
}
if (panel == NULL) {
printf("ERROR: missing ptr to am335x_lcdpanel!\n");
return -1;
}
/* We can already set the bits for the raster_ctrl in this check */
switch (panel->bpp) {
case 16:
break;
case 32:
raster_ctrl |= LCD_TFT_24BPP_UNPACK;
/* fallthrough */
case 24:
raster_ctrl |= LCD_TFT_24BPP_MODE;
break;
default:
pr_err("am335x-fb: invalid bpp value: %d\n", panel->bpp);
return -1;
}
/* check given clock-frequency */
if (panel->pxl_clk > (LCDC_FMAX / 2)) {
pr_err("am335x-fb: requested pxl-clk: %d not supported!\n",
panel->pxl_clk);
return -1;
}
debug("setting up LCD-Controller for %dx%dx%d (hfp=%d,hbp=%d,hsw=%d / ",
panel->hactive, panel->vactive, panel->bpp,
panel->hfp, panel->hbp, panel->hsw);
debug("vfp=%d,vbp=%d,vsw=%d / clk=%d)\n",
panel->vfp, panel->vfp, panel->vsw, panel->pxl_clk);
debug("using frambuffer at 0x%08x with size %d.\n",
(unsigned int)gd->fb_base, FBSIZE(panel));
/* setup display pll for requested clock frequency */
err = panel->pxl_clk;
err_r = err;
for (d = 2; d < 255; d++) {
for (m = 2; m < 2047; m++) {
if ((V_OSCK * m) < (panel->pxl_clk * d))
continue;
n = (V_OSCK * m) / (panel->pxl_clk * d);
if (n > 127)
break;
if (((V_OSCK * m) / n) > LCDC_FMAX)
break;
err = abs((V_OSCK * m) / n / d - panel->pxl_clk);
if (err < err_r) {
err_r = err;
dpll_disp.m = m;
dpll_disp.n = n;
best_d = d;
}
}
}
debug("%s: PLL: best error %d Hz (M %d, N %d, DISP %d)\n",
__func__, err_r, dpll_disp.m, dpll_disp.n, best_d);
do_setup_dpll(&dpll_disp_regs, &dpll_disp);
/* clock source for LCDC from dispPLL M2 */
writel(0x0, &cmdpll->clklcdcpixelclk);
/* palette default entry */
memset((void *)gd->fb_base, 0, 0x20);
*(unsigned int *)gd->fb_base = 0x4000;
/* point fb behind palette */
gd->fb_base += 0x20;
/* turn ON display through powercontrol function if accessible */
if (panel->panel_power_ctrl != NULL)
panel->panel_power_ctrl(1);
debug("am335x-fb: wait for stable power ...\n");
mdelay(panel->pup_delay);
lcdhw->clkc_enable = LCD_CORECLKEN | LCD_LIDDCLKEN | LCD_DMACLKEN;
lcdhw->raster_ctrl = 0;
lcdhw->ctrl = LCD_CLK_DIVISOR(best_d) | LCD_RASTER_MODE;
lcdhw->lcddma_fb0_base = gd->fb_base;
lcdhw->lcddma_fb0_ceiling = gd->fb_base + FBSIZE(panel);
lcdhw->lcddma_fb1_base = gd->fb_base;
lcdhw->lcddma_fb1_ceiling = gd->fb_base + FBSIZE(panel);
lcdhw->lcddma_ctrl = LCD_DMA_BURST_SIZE(LCD_DMA_BURST_16);
lcdhw->raster_timing0 = LCD_HORLSB(panel->hactive) |
LCD_HORMSB(panel->hactive) |
LCD_HFPLSB(panel->hfp) |
LCD_HBPLSB(panel->hbp) |
LCD_HSWLSB(panel->hsw);
lcdhw->raster_timing1 = LCD_VBP(panel->vbp) |
LCD_VFP(panel->vfp) |
LCD_VSW(panel->vsw) |
LCD_VERLSB(panel->vactive);
lcdhw->raster_timing2 = LCD_HSWMSB(panel->hsw) |
LCD_VERMSB(panel->vactive) |
LCD_INVMASK(panel->pol) |
LCD_HBPMSB(panel->hbp) |
LCD_HFPMSB(panel->hfp) |
0x0000FF00; /* clk cycles for ac-bias */
lcdhw->raster_ctrl = raster_ctrl |
LCD_PALMODE_RAWDATA |
LCD_TFT_MODE |
LCD_RASTER_ENABLE;
debug("am335x-fb: waiting picture to be stable.\n.");
mdelay(panel->pon_delay);
return 0;
}