Hi Marten, On 11/10/21 8:05 PM, Mårten Lindahl wrote: > The TMOUT register is always set with a full value for every transfer, > which (with a 200MHz clock) will give a full DRTO of ~84 milliseconds. > Since the software dto_timer acts as a backup in cases when this timeout > is not long enough, it is normally not a problem. But setting a full > value makes it impossible to test shorter timeouts, when for example > testing data read times on different SD cards. > > Add a function to set any value smaller than the maximum of 0xFFFFFF. > > Signed-off-by: Mårten Lindahl <marten.lindahl@xxxxxxxx> Reviewed-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx> Best Regards, Jaehoon Chung > --- > > v2: > - Calculate new value before checking boundaries > - Include CLKDIV register to get proper value > > v3: > - Use 'if-else' instead of 'goto' > - Don't touch response field when maximize data field > > drivers/mmc/host/dw_mmc.c | 28 +++++++++++++++++++++++++++- > 1 file changed, 27 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c > index 6578cc64ae9e..637ae2aea9fa 100644 > --- a/drivers/mmc/host/dw_mmc.c > +++ b/drivers/mmc/host/dw_mmc.c > @@ -1283,6 +1283,32 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot, bool force_clkinit) > mci_writel(host, CTYPE, (slot->ctype << slot->id)); > } > > +static void dw_mci_set_data_timeout(struct dw_mci *host, > + unsigned int timeout_ns) > +{ > + unsigned int clk_div, tmp, tmout; > + > + clk_div = (mci_readl(host, CLKDIV) & 0xFF) * 2; > + if (clk_div == 0) > + clk_div = 1; > + > + tmp = DIV_ROUND_UP_ULL((u64)timeout_ns * host->bus_hz, > + NSEC_PER_SEC * clk_div); > + > + /* TMOUT[7:0] (RESPONSE_TIMEOUT) */ > + tmout = 0xFF; /* Set maximum */ > + > + /* TMOUT[31:8] (DATA_TIMEOUT) */ > + if (!tmp || tmp > 0xFFFFFF) > + tmout |= (0xFFFFFF << 8); > + else > + tmout |= (tmp & 0xFFFFFF) << 8; > + > + mci_writel(host, TMOUT, tmout); > + dev_dbg(host->dev, "timeout_ns: %u => TMOUT[31:8]: 0x%06x", > + timeout_ns, tmout >> 8); > +} > + > static void __dw_mci_start_request(struct dw_mci *host, > struct dw_mci_slot *slot, > struct mmc_command *cmd) > @@ -1303,7 +1329,7 @@ static void __dw_mci_start_request(struct dw_mci *host, > > data = cmd->data; > if (data) { > - mci_writel(host, TMOUT, 0xFFFFFFFF); > + dw_mci_set_data_timeout(host, data->timeout_ns); > mci_writel(host, BYTCNT, data->blksz*data->blocks); > mci_writel(host, BLKSIZ, data->blksz); > } >