From 01c40a17249727472da3f52e2f344cc2cc4138c4 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Mon, 8 Oct 2018 12:57:35 +0200 Subject: mach64: optimize wait_for_fifo MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is a simple optimization for fifo waiting that improves scrolling performance by 5%. If the queue has more free entries that what we consume, we can skip the costly register read next time. Signed-off-by: Mikulas Patocka Reviewed-by: Ville Syrjälä Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/video/fbdev/aty/atyfb.h | 12 ++++++++---- drivers/video/fbdev/aty/mach64_accel.c | 4 +++- 2 files changed, 11 insertions(+), 5 deletions(-) (limited to 'drivers/video') diff --git a/drivers/video/fbdev/aty/atyfb.h b/drivers/video/fbdev/aty/atyfb.h index d09bab3bf224..e5a347c58180 100644 --- a/drivers/video/fbdev/aty/atyfb.h +++ b/drivers/video/fbdev/aty/atyfb.h @@ -147,6 +147,7 @@ struct atyfb_par { u16 pci_id; u32 accel_flags; int blitter_may_be_busy; + unsigned fifo_space; int asleep; int lock_blank; unsigned long res_start; @@ -346,10 +347,13 @@ extern int aty_init_cursor(struct fb_info *info); * Hardware acceleration */ -static inline void wait_for_fifo(u16 entries, const struct atyfb_par *par) +static inline void wait_for_fifo(u16 entries, struct atyfb_par *par) { - while ((aty_ld_le32(FIFO_STAT, par) & 0xffff) > - ((u32) (0x8000 >> entries))); + unsigned fifo_space = par->fifo_space; + while (entries > fifo_space) { + fifo_space = 16 - fls(aty_ld_le32(FIFO_STAT, par) & 0xffff); + } + par->fifo_space = fifo_space - entries; } static inline void wait_for_idle(struct atyfb_par *par) @@ -359,7 +363,7 @@ static inline void wait_for_idle(struct atyfb_par *par) par->blitter_may_be_busy = 0; } -extern void aty_reset_engine(const struct atyfb_par *par); +extern void aty_reset_engine(struct atyfb_par *par); extern void aty_init_engine(struct atyfb_par *par, struct fb_info *info); void atyfb_copyarea(struct fb_info *info, const struct fb_copyarea *area); diff --git a/drivers/video/fbdev/aty/mach64_accel.c b/drivers/video/fbdev/aty/mach64_accel.c index 3ad46255f990..e4b2c89baee2 100644 --- a/drivers/video/fbdev/aty/mach64_accel.c +++ b/drivers/video/fbdev/aty/mach64_accel.c @@ -37,7 +37,7 @@ static u32 rotation24bpp(u32 dx, u32 direction) return ((rotation << 8) | DST_24_ROTATION_ENABLE); } -void aty_reset_engine(const struct atyfb_par *par) +void aty_reset_engine(struct atyfb_par *par) { /* reset engine */ aty_st_le32(GEN_TEST_CNTL, @@ -50,6 +50,8 @@ void aty_reset_engine(const struct atyfb_par *par) /* HOST errors */ aty_st_le32(BUS_CNTL, aty_ld_le32(BUS_CNTL, par) | BUS_HOST_ERR_ACK | BUS_FIFO_ERR_ACK, par); + + par->fifo_space = 0; } static void reset_GTC_3D_engine(const struct atyfb_par *par) -- cgit v1.2.3