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H300: (1) Use DMA for LCD updates, with auto-aligned line reads. Speeds up LCD updates by ~ 75% at 11MHz and 45MHz. Only ~ 11% speedup at 124MHz due to (2). (2) Less aggressive LCD transfer timing at 124MHz. With the previous timing, slightly corrupted display contents was reported, and with DMA transfers at least 4 waitstates are needed to make updates work at all. * A table in system-iriver.c shows settings for all integer multiples of the base clock frequency (info for developers, not yet complete).

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@11418 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jens Arnold 2006-11-02 20:50:50 +00:00
parent d86350c9fa
commit 83aded979f
4 changed files with 59 additions and 110 deletions
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48
firmware/drivers/lcd-h300.c
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@ -368,7 +368,16 @@ void lcd_update(void)
/* Copy display bitmap to hardware */
lcd_write_reg(R_RAM_ADDR_SET, xoffset << 8);
lcd_begin_write_gram();
lcd_write_data((unsigned short *)lcd_framebuffer, LCD_WIDTH*LCD_HEIGHT);
DAR3 = 0xf0000002;
SAR3 = (unsigned long)lcd_framebuffer;
BCR3 = LCD_WIDTH*LCD_HEIGHT*2;
DCR3 = DMA_AA | DMA_BWC(1)
| DMA_SINC | DMA_SSIZE(DMA_SIZE_LINE)
| DMA_DSIZE(DMA_SIZE_WORD) | DMA_START;
while (!(DSR3 & 1));
DSR3 = 1;
}
}
@ -376,26 +385,39 @@ void lcd_update(void)
void lcd_update_rect(int, int, int, int) ICODE_ATTR;
void lcd_update_rect(int x, int y, int width, int height)
{
unsigned long dma_addr;
if(display_on) {
int ymax = y + height - 1;
if(x + width > LCD_WIDTH)
width = LCD_WIDTH - x;
if (width <= 0)
return; /* nothing left to do, 0 is harmful to lcd_write_data() */
if(ymax >= LCD_HEIGHT)
ymax = LCD_HEIGHT-1;
if(width <= 0) /* nothing to do */
return;
if(y + height > LCD_HEIGHT)
height = LCD_HEIGHT - y;
/* set update window */
/* set update window */
lcd_write_reg(R_VERT_RAM_ADDR_POS,((x+xoffset+width-1) << 8) | (x+xoffset));
lcd_write_reg(R_RAM_ADDR_SET, ((x+xoffset) << 8) | y);
lcd_begin_write_gram();
lcd_begin_write_gram();
DAR3 = 0xf0000002;
dma_addr = (unsigned long)&lcd_framebuffer[y][x];
width *= 2;
/* Copy specified rectangle bitmap to hardware */
for (; y <= ymax; y++)
{
lcd_write_data ((unsigned short *)&lcd_framebuffer[y][x], width);
}
for (; height > 0; height--)
{
SAR3 = dma_addr;
BCR3 = width;
DCR3 = DMA_AA | DMA_BWC(1)
| DMA_SINC | DMA_SSIZE(DMA_SIZE_LINE)
| DMA_DSIZE(DMA_SIZE_WORD) | DMA_START;
dma_addr += LCD_WIDTH*2;
while (!(DSR3 & 1));
DSR3 = 1;
}
}
}