Message ID | 1514924097-1630-1-git-send-email-kdasu.kdev@gmail.com |
---|---|
State | Superseded |
Delegated to: | Boris Brezillon |
Headers | show |
Series | mtd: brcmnand: Disable prefetch by default | expand |
Hi Kamal, The prefix should be "mtd: nand: brcmnand: ". On Tue, 2 Jan 2018 15:14:57 -0500 Kamal Dasu <kdasu.kdev@gmail.com> wrote: > Brcm nand controller prefetch feature needs to be disabled > by default. Enabling effects performance on random reads as ^ affects ? > well as dma reads. > > Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> Maybe Fixes and CC-stable tags would be relevant here, unless you don't consider this patch as a fix and don't want to backport it to stable kernels. > --- > drivers/mtd/nand/brcmnand/brcmnand.c | 13 +++---------- > 1 file changed, 3 insertions(+), 10 deletions(-) > > diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c > index dd56a67..2a978d9 100644 > --- a/drivers/mtd/nand/brcmnand/brcmnand.c > +++ b/drivers/mtd/nand/brcmnand/brcmnand.c > @@ -2193,16 +2193,9 @@ static int brcmnand_setup_dev(struct brcmnand_host *host) > if (ctrl->nand_version >= 0x0702) > tmp |= ACC_CONTROL_RD_ERASED; > tmp &= ~ACC_CONTROL_FAST_PGM_RDIN; > - if (ctrl->features & BRCMNAND_HAS_PREFETCH) { > - /* > - * FIXME: Flash DMA + prefetch may see spurious erased-page ECC > - * errors > - */ > - if (has_flash_dma(ctrl)) > - tmp &= ~ACC_CONTROL_PREFETCH; > - else > - tmp |= ACC_CONTROL_PREFETCH; > - } > + if (ctrl->features & BRCMNAND_HAS_PREFETCH) > + tmp &= ~ACC_CONTROL_PREFETCH; > + > nand_writereg(ctrl, offs, tmp); > > return 0;
diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c index dd56a67..2a978d9 100644 --- a/drivers/mtd/nand/brcmnand/brcmnand.c +++ b/drivers/mtd/nand/brcmnand/brcmnand.c @@ -2193,16 +2193,9 @@ static int brcmnand_setup_dev(struct brcmnand_host *host) if (ctrl->nand_version >= 0x0702) tmp |= ACC_CONTROL_RD_ERASED; tmp &= ~ACC_CONTROL_FAST_PGM_RDIN; - if (ctrl->features & BRCMNAND_HAS_PREFETCH) { - /* - * FIXME: Flash DMA + prefetch may see spurious erased-page ECC - * errors - */ - if (has_flash_dma(ctrl)) - tmp &= ~ACC_CONTROL_PREFETCH; - else - tmp |= ACC_CONTROL_PREFETCH; - } + if (ctrl->features & BRCMNAND_HAS_PREFETCH) + tmp &= ~ACC_CONTROL_PREFETCH; + nand_writereg(ctrl, offs, tmp); return 0;
Brcm nand controller prefetch feature needs to be disabled by default. Enabling effects performance on random reads as well as dma reads. Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> --- drivers/mtd/nand/brcmnand/brcmnand.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-)