mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
drm: lcdif: change burst size to 256B
If a axi bus master with a higher priority do a lot of memory access
FIFO underruns can be inspected. Increase the burst size to 256B to
avoid such underruns and to improve the memory access efficiency.
Fixes: 9db35bb349
("drm: lcdif: Add support for i.MX8MP LCDIF variant")
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20221101164615.778299-1-m.felsch@pengutronix.de
This commit is contained in:
parent
da7ffb9660
commit
2215cb3be5
2 changed files with 16 additions and 2 deletions
|
@ -314,8 +314,18 @@ static void lcdif_set_mode(struct lcdif_drm_private *lcdif, u32 bus_flags)
|
|||
CTRLDESCL0_1_WIDTH(m->hdisplay),
|
||||
lcdif->base + LCDC_V8_CTRLDESCL0_1);
|
||||
|
||||
writel(CTRLDESCL0_3_PITCH(lcdif->crtc.primary->state->fb->pitches[0]),
|
||||
lcdif->base + LCDC_V8_CTRLDESCL0_3);
|
||||
/*
|
||||
* Undocumented P_SIZE and T_SIZE register but those written in the
|
||||
* downstream kernel those registers control the AXI burst size. As of
|
||||
* now there are two known values:
|
||||
* 1 - 128Byte
|
||||
* 2 - 256Byte
|
||||
* Downstream set it to 256B burst size to improve the memory
|
||||
* efficiency so set it here too.
|
||||
*/
|
||||
ctrl = CTRLDESCL0_3_P_SIZE(2) | CTRLDESCL0_3_T_SIZE(2) |
|
||||
CTRLDESCL0_3_PITCH(lcdif->crtc.primary->state->fb->pitches[0]);
|
||||
writel(ctrl, lcdif->base + LCDC_V8_CTRLDESCL0_3);
|
||||
}
|
||||
|
||||
static void lcdif_enable_controller(struct lcdif_drm_private *lcdif)
|
||||
|
|
|
@ -190,6 +190,10 @@
|
|||
#define CTRLDESCL0_1_WIDTH(n) ((n) & 0xffff)
|
||||
#define CTRLDESCL0_1_WIDTH_MASK GENMASK(15, 0)
|
||||
|
||||
#define CTRLDESCL0_3_P_SIZE(n) (((n) << 20) & CTRLDESCL0_3_P_SIZE_MASK)
|
||||
#define CTRLDESCL0_3_P_SIZE_MASK GENMASK(22, 20)
|
||||
#define CTRLDESCL0_3_T_SIZE(n) (((n) << 16) & CTRLDESCL0_3_T_SIZE_MASK)
|
||||
#define CTRLDESCL0_3_T_SIZE_MASK GENMASK(17, 16)
|
||||
#define CTRLDESCL0_3_PITCH(n) ((n) & 0xffff)
|
||||
#define CTRLDESCL0_3_PITCH_MASK GENMASK(15, 0)
|
||||
|
||||
|
|
Loading…
Reference in a new issue