Re: [PATCH v2 2/2] i2c: qcom-geni: add I2C frequency table for 32 MHz firmware-based SEs

[Kathiravan Thirumoorthy]

On 8/24/2026 2:54 PM, Konrad Dybcio wrote:
> On 8/12/26 10:30 AM, Kathiravan Thirumoorthy wrote:
> > On IPQ5424, the I2C controller can operate on both RTL-hardened SEs
> > and firmware-based SEs. As documented in commit 506bb2ab0075
> > ("i2c: qcom-geni: Support systems with 32MHz serial engine clock"),
> > in IPQ5424 SEs use a 32 MHz source clock.
> >
> > The existing frequency table does not provide the required SCL timing
> > parameters for firmware-based SEs. Add a dedicated frequency table
> > using the SCL counter values recommended by the hardware design team
> > and select it for firmware-based SEs to achieve the target bus
> > frequencies.
> >
> > Move geni_i2c_clk_map_idx() from geni_i2c_resources_init() to
> > geni_i2c_init() to ensure SE_HW_PARAM_2 is accessed only after the
> > required clocks have been enabled.
> >
> > Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@xxxxxxxxxxxxxxxx>
> > ---
> >   drivers/i2c/busses/i2c-qcom-geni.c | 25 ++++++++++++++++++-------
> >   include/linux/soc/qcom/geni-se.h   |  1 +
> >   2 files changed, 19 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> > index 00013b41a6f5..15835f10b062 100644
> > --- a/drivers/i2c/busses/i2c-qcom-geni.c
> > +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> > @@ -187,19 +187,28 @@ static const struct geni_i2c_clk_fld geni_i2c_clk_map_19p2mhz[] = {
> >   };
> >   
> >   /* source_clock = 32 MHz */
> > -static const struct geni_i2c_clk_fld geni_i2c_clk_map_32mhz[] = {
> > +static const struct geni_i2c_clk_fld geni_i2c_clk_map_32mhz_minicore[] = {
> >   	{ I2C_MAX_STANDARD_MODE_FREQ, 12, 9, 10, 26 },
> >   	{ I2C_MAX_FAST_MODE_FREQ, 4, 3, 9, 19 },
> >   	{ I2C_MAX_FAST_MODE_PLUS_FREQ, 2, 3, 5, 15 },
> >   	{}
> >   };
> >   
> > +static const struct geni_i2c_clk_fld geni_i2c_clk_map_32mhz_fwcore[] = {
> > +	{ I2C_MAX_STANDARD_MODE_FREQ, 12, 9, 10, 25 },
> > +	{ I2C_MAX_FAST_MODE_FREQ, 4, 3, 9, 18 },
> > +	{ I2C_MAX_FAST_MODE_PLUS_FREQ, 1, 6, 15, 29 },
> > +	{}
> > +};
> The fwcore one seems to be slightly "stricter" - wouldn't it work
> for both of them?

No, We are not able to achieve the desired frequency. So based on design 
team's feedback, we are using separate configurations.

> Konrad