On 09/23/2011 11:12 AM, Marek Vasut wrote: Hi Marek,
> mxc_ata.c: In function ‘set_ata_bus_timing’: > mxc_ata.c:118: warning: dereferencing type-punned pointer will break > strict-aliasing rules > mxc_ata.c:125: warning: dereferencing type-punned pointer will break > strict-aliasing rules > mxc_ata.c:129: warning: dereferencing type-punned pointer will break > strict-aliasing rules > > Signed-off-by: Marek Vasut <[email protected]> > Cc: Stefano Babic <[email protected]> > --- > drivers/block/mxc_ata.c | 10 +++++++--- > 1 files changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/block/mxc_ata.c b/drivers/block/mxc_ata.c > index f22f4f4..d94ec9c 100644 > --- a/drivers/block/mxc_ata.c > +++ b/drivers/block/mxc_ata.c > @@ -98,6 +98,7 @@ static void set_ata_bus_timing(unsigned char mode) > { > uint32_t val; > uint32_t T = 1000000000 / mxc_get_clock(MXC_IPG_CLK); > + uint32_t reg; > > struct mxc_ata_config_regs *ata_regs; > ata_regs = (struct mxc_ata_config_regs *)CONFIG_SYS_ATA_BASE_ADDR; > @@ -106,22 +107,25 @@ static void set_ata_bus_timing(unsigned char mode) > return; > > /* Write TIME_OFF/ON/1/2W */ > + reg = (uint32_t)&ata_regs->time_off; You drop the warnings using casting, but is it correct ? time_off is defined as u8 (correctly, because this is the size of the register). If you write 32bit, you risk to overwrite the time_on, time_1 and time_2w registers. Why do not use writeb ? > val = (3 << REG2OFF(&ata_regs->time_off)) | > (3 << REG2OFF(&ata_regs->time_on)) | > (((pio_t1[mode] + T) / T) << REG2OFF(&ata_regs->time_1)) | > (((pio_t2_8[mode] + T) / T) << REG2OFF(&ata_regs->time_2w)); > - writel(val, &ata_regs->time_off); > + writel(val, reg); Understood. You *want* to write all registers in one shot. However this is hackish. Or you write each register separetely, or you use a union to access the register block with a 32 bit access. Everybody reading "writel(val, &ata_regs->time_off)" expects that time_off is 32bit wide. Best regards, Stefano Babic -- ===================================================================== DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: [email protected] ===================================================================== _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
