From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Andreas_Bie=c3=9fmann?= Date: Tue, 1 Dec 2015 17:52:39 +0100 Subject: [U-Boot] [PATCH v2] mmc: atmel: Properly fix clock configuration In-Reply-To: <1446753510-16783-1-git-send-email-gregory.clement@free-electrons.com> References: <1446753510-16783-1-git-send-email-gregory.clement@free-electrons.com> Message-ID: <565DD057.5080509@biessmann.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Pantelis, On 05.11.15 20:58, Gregory CLEMENT wrote: > Timing issue occurs on eMMC not only when modifying the frequency but > also for all the switch command(CMD6). According to the MMC spec waiting > 8 clocks after a switch command would be the thing to do. > > This patch allows fixing CPU hang observed when trying to changing the > bus width on a eMMC on SAMA5D4. > > Signed-off-by: Gregory CLEMENT > Tested-by: Marek Vasut # on DENX MA5D4EV this patch [1] is delegated to you on patchwork ... will you take it? Andreas [1] http://patchwork.ozlabs.org/patch/540686/ > --- > drivers/mmc/gen_atmel_mci.c | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/mmc/gen_atmel_mci.c b/drivers/mmc/gen_atmel_mci.c > index da870c6..f090b27 100644 > --- a/drivers/mmc/gen_atmel_mci.c > +++ b/drivers/mmc/gen_atmel_mci.c > @@ -36,6 +36,7 @@ struct atmel_mci_priv { > struct mmc_config cfg; > struct atmel_mci *mci; > unsigned int initialized:1; > + unsigned int curr_clk; > }; > > /* Read Atmel MCI IP version */ > @@ -91,7 +92,10 @@ static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen) > > } > } > - > + if (version >= 0x500) > + priv->curr_clk = bus_hz / (clkdiv * 2 + clkodd + 2); > + else > + priv->curr_clk = (bus_hz / (clkdiv + 1)) / 2; > blklen &= 0xfffc; > > mr = MMCI_BF(CLKDIV, clkdiv); > @@ -118,8 +122,6 @@ static void mci_set_mode(struct mmc *mmc, u32 hz, u32 blklen) > if (mmc->card_caps & mmc->cfg->host_caps & MMC_MODE_HS) > writel(MMCI_BIT(HSMODE), &mci->cfg); > > - udelay(50); > - > priv->initialized = 1; > } > > @@ -323,6 +325,13 @@ mci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data) > } > } > > + /* > + * After the switch command, wait for 8 clocks before the next > + * command > + */ > + if (cmd->cmdidx == MMC_CMD_SWITCH) > + udelay(8*1000000/ priv->curr_clk); /* 8 clk in us */ > + > return 0; > } > > -------------- next part -------------- A non-text attachment was scrubbed... Name: 0xBC2469C7.asc Type: application/pgp-keys Size: 36384 bytes Desc: not available URL: