[U-Boot] [PATCH 4/5] cm-t35: add support for user defined lcd parameters

Nikita Kiryanov
2012-12-23T07:03:47Z

Add support for user defined lcd parameters for cm-t35 splash screen.

Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
---
board/cm_t35/display.c | 213 +++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 210 insertions(+), 3 deletions(-)

diff --git a/board/cm_t35/display.c b/board/cm_t35/display.c
index 11b8ed9..7b09bce 100644
--- a/board/cm_t35/display.c
+++ b/board/cm_t35/display.c
@@ -3,6 +3,8 @@
*
* Authors: Nikita Kiryanov <nikita@compulab.co.il>
*
+ * Parsing code based on linux/drivers/video/pxafb.c
+ *
* See file CREDITS for list of people who contributed to this
* project.
*
@@ -33,6 +35,7 @@ DECLARE_GLOBAL_DATA_PTR;
enum display_type {
NONE,
DVI,
+ DVI_CUSTOM,
};

/*
@@ -138,6 +141,205 @@ static enum display_type set_dvi_preset(const struct panel_config preset,
}

/*
+ * parse_mode() - parse the mode parameter of custom lcd settings
+ *
+ * @mode: <res_x>x<res_y>
+ *
+ * Returns -1 on error, 0 on success.
+ */
+static int parse_mode(const char *mode)
+{
+ unsigned int modelen = strlen(mode);
+ int res_specified = 0;
+ unsigned int xres = 0, yres = 0;
+ int yres_specified = 0;
+ int i;
+
+ for (i = modelen - 1; i >= 0; i--) {
+ switch (mode[i]) {
+ case 'x':
+ if (!yres_specified) {
+ yres = simple_strtoul(&mode[i + 1], NULL, 0);
+ yres_specified = 1;
+ } else {
+ goto done_parsing;
+ }
+
+ break;
+ case '0' ... '9':
+ break;
+ default:
+ goto done_parsing;
+ }
+ }
+
+ if (i < 0 && yres_specified) {
+ xres = simple_strtoul(mode, NULL, 0);
+ res_specified = 1;
+ }
+
+done_parsing:
+ if (res_specified) {
+ set_resolution_params(xres, yres);
+ } else {
+ printf("LCD: invalid mode: %s\n", mode);
+ return -1;
+ }
+
+ return 0;
+}
+
+#define PIXEL_CLK_NUMERATOR (26 * 432 / 39)
+/*
+ * parse_pixclock() - Parse the pixclock parameter of custom lcd settings
+ *
+ * @pixclock: the desired pixel clock
+ *
+ * Returns -1 on error, 0 on success.
+ *
+ * Handling the pixel_clock:
+ *
+ * Pixel clock is defined in the OMAP35x TRM as follows:
+ * pixel_clock =
+ * (SYS_CLK * 2 * PRCM.CM_CLKSEL2_PLL[18:8]) /
+ * (DSS.DISPC_DIVISOR[23:16] * DSS.DISPC_DIVISOR[6:0] *
+ * PRCM.CM_CLKSEL_DSS[4:0] * (PRCM.CM_CLKSEL2_PLL[6:0] + 1))
+ *
+ * In practice, this means that in order to set the
+ * divisor for the desired pixel clock one needs to
+ * solve the following equation:
+ *
+ * 26 * 432 / (39 * <pixel_clock>) = DSS.DISPC_DIVISOR[6:0]
+ *
+ * NOTE: the explicit equation above is reduced. Do not
+ * try to infer anything from these numbers.
+ */
+static int parse_pixclock(char *pixclock)
+{
+ int divisor, pixclock_val;
+ char *pixclk_start = pixclock;
+
+ pixclock_val = simple_strtoul(pixclock, &pixclock, 10);
+ divisor = DIV_ROUND_UP(PIXEL_CLK_NUMERATOR, pixclock_val);
+ /* 0 and 1 are illegal values for PCD */
+ if (divisor <= 1)
+ divisor = 2;
+
+ panel_cfg.divisor = divisor | (1 << 16);
+ if (pixclock[0] != '\0') {
+ printf("LCD: invalid value for pixclock:%s\n", pixclk_start);
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * parse_setting() - parse a single setting of custom lcd parameters
+ *
+ * @setting: The custom lcd setting <name>:<value>
+ *
+ * Returns -1 on failure, 0 on success.
+ */
+static int parse_setting(char *setting)
+{
+ int num_val;
+ char *setting_start = setting;
+
+ if (!strncmp(setting, "mode:", 5)) {
+ return parse_mode(setting + 5);
+ } else if (!strncmp(setting, "pixclock:", 9)) {
+ return parse_pixclock(setting + 9);
+ } else if (!strncmp(setting, "left:", 5)) {
+ num_val = simple_strtoul(setting + 5, &setting, 0);
+ panel_cfg.timing_h |= DSS_HBP(num_val);
+ } else if (!strncmp(setting, "right:", 6)) {
+ num_val = simple_strtoul(setting + 6, &setting, 0);
+ panel_cfg.timing_h |= DSS_HFP(num_val);
+ } else if (!strncmp(setting, "upper:", 6)) {
+ num_val = simple_strtoul(setting + 6, &setting, 0);
+ panel_cfg.timing_v |= DSS_VBP(num_val);
+ } else if (!strncmp(setting, "lower:", 6)) {
+ num_val = simple_strtoul(setting + 6, &setting, 0);
+ panel_cfg.timing_v |= DSS_VFP(num_val);
+ } else if (!strncmp(setting, "hsynclen:", 9)) {
+ num_val = simple_strtoul(setting + 9, &setting, 0);
+ panel_cfg.timing_h |= DSS_HSW(num_val);
+ } else if (!strncmp(setting, "vsynclen:", 9)) {
+ num_val = simple_strtoul(setting + 9, &setting, 0);
+ panel_cfg.timing_v |= DSS_VSW(num_val);
+ } else if (!strncmp(setting, "hsync:", 6)) {
+ if (simple_strtoul(setting + 6, &setting, 0) == 0)
+ panel_cfg.pol_freq |= DSS_IHS;
+ else
+ panel_cfg.pol_freq &= ~DSS_IHS;
+ } else if (!strncmp(setting, "vsync:", 6)) {
+ if (simple_strtoul(setting + 6, &setting, 0) == 0)
+ panel_cfg.pol_freq |= DSS_IVS;
+ else
+ panel_cfg.pol_freq &= ~DSS_IVS;
+ } else if (!strncmp(setting, "outputen:", 9)) {
+ if (simple_strtoul(setting + 9, &setting, 0) == 0)
+ panel_cfg.pol_freq |= DSS_IEO;
+ else
+ panel_cfg.pol_freq &= ~DSS_IEO;
+ } else if (!strncmp(setting, "pixclockpol:", 12)) {
+ if (simple_strtoul(setting + 12, &setting, 0) == 0)
+ panel_cfg.pol_freq |= DSS_IPC;
+ else
+ panel_cfg.pol_freq &= ~DSS_IPC;
+ } else if (!strncmp(setting, "active", 6)) {
+ panel_cfg.panel_type = ACTIVE_DISPLAY;
+ return 0; /* Avoid sanity check below */
+ } else if (!strncmp(setting, "passive", 7)) {
+ panel_cfg.panel_type = PASSIVE_DISPLAY;
+ return 0; /* Avoid sanity check below */
+ } else if (!strncmp(setting, "display:", 8)) {
+ if (!strncmp(setting + 8, "dvi", 3)) {
+ lcd_def = DVI_CUSTOM;
+ return 0; /* Avoid sanity check below */
+ }
+ } else {
+ printf("LCD: unknown option %s\n", setting_start);
+ return -1;
+ }
+
+ if (setting[0] != '\0') {
+ printf("LCD: invalid value for %s\n", setting_start);
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * env_parse_customlcd() - parse custom lcd params from an environment variable.
+ *
+ * @custom_lcd_params: The environment variable containing the lcd params.
+ *
+ * Returns -1 on failure, 0 on success.
+ */
+static int parse_customlcd(char *custom_lcd_params)
+{
+ char params_cpy[160];
+ char *setting;
+
+ strncpy(params_cpy, custom_lcd_params, 160);
+ setting = strtok(params_cpy, ",");
+ while (setting) {
+ if (parse_setting(setting) < 0)
+ return -1;
+
+ setting = strtok(NULL, ",");
+ }
+
+ /* Currently we don't support changing this via custom lcd params */
+ panel_cfg.data_lines = LCD_INTERFACE_24_BIT;
+
+ return 0;
+}
+
+/*
* env_parse_displaytype() - parse display type.
*
* Parses the environment variable "displaytype", which contains the
@@ -176,14 +378,19 @@ void lcd_ctrl_init(void *lcdbase)
{
struct dispc_regs *dispc = (struct dispc_regs *)OMAP3_DISPC_BASE;
struct prcm *prcm = (struct prcm *)PRCM_BASE;
+ char *custom_lcd;
char *displaytype = getenv("displaytype");

if (displaytype == NULL)
return;

lcd_def = env_parse_displaytype(displaytype);
- if (lcd_def == NONE)
- return;
+ /* If we did not recognize the preset, check if it's an env variable */
+ if (lcd_def == NONE) {
+ custom_lcd = getenv(displaytype);
+ if (custom_lcd == NULL || parse_customlcd(custom_lcd) < 0)
+ return;
+ }

panel_cfg.frame_buffer = lcdbase;
omap3_dss_panel_config(&panel_cfg);
@@ -204,7 +411,7 @@ void lcd_ctrl_init(void *lcdbase)

void lcd_enable(void)
{
- if (lcd_def == DVI) {
+ if (lcd_def == DVI || lcd_def == DVI_CUSTOM) {
gpio_direction_output(54, 0); /* Turn on DVI */
omap3_dss_enable();
}
--
1.7.10.4