| Message ID | 1642080623-15980-2-git-send-email-akhilrajeev@nvidia.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add I2C and PWM support for T234 | expand |
13.01.2022 16:30, Akhil R пишет: > +static const struct tegra_i2c_hw_feature tegra234_i2c_hw = { > + .has_continue_xfer_support = true, > + .has_per_pkt_xfer_complete_irq = true, > + .clk_divisor_hs_mode = 0x2, > + .clk_divisor_std_mode = 0x4f, > + .clk_divisor_fast_mode = 0x58, > + .clk_divisor_fast_plus_mode = 0x24, > + .has_config_load_reg = true, > + .has_multi_master_mode = true, > + .has_slcg_override_reg = true, > + .has_mst_fifo = true, > + .quirks = &tegra194_i2c_quirks, > + .supports_bus_clear = true, > + .has_apb_dma = false, > + .tlow_std_mode = 0x8, > + .thigh_std_mode = 0x7, > + .tlow_fast_fastplus_mode = 0x1, > + .thigh_fast_fastplus_mode = 0x1, > + .setup_hold_time_std_mode = 0x08080808, > + .setup_hold_time_fast_fast_plus_mode = 0x02020202, > + .setup_hold_time_hs_mode = 0x090909, > + .has_interface_timing_reg = true, > +}; Why tegra194_i2c_hw can't be reused by T234? Looks like I2C h/w hasn't changed and somebody just made a minor tuning of the timing parameters, does it really matter in practice?
> 13.01.2022 16:30, Akhil R пишет: > > +static const struct tegra_i2c_hw_feature tegra234_i2c_hw = { > > + .has_continue_xfer_support = true, > > + .has_per_pkt_xfer_complete_irq = true, > > + .clk_divisor_hs_mode = 0x2, > > + .clk_divisor_std_mode = 0x4f, > > + .clk_divisor_fast_mode = 0x58, > > + .clk_divisor_fast_plus_mode = 0x24, > > + .has_config_load_reg = true, > > + .has_multi_master_mode = true, > > + .has_slcg_override_reg = true, > > + .has_mst_fifo = true, > > + .quirks = &tegra194_i2c_quirks, > > + .supports_bus_clear = true, > > + .has_apb_dma = false, > > + .tlow_std_mode = 0x8, > > + .thigh_std_mode = 0x7, > > + .tlow_fast_fastplus_mode = 0x1, > > + .thigh_fast_fastplus_mode = 0x1, > > + .setup_hold_time_std_mode = 0x08080808, > > + .setup_hold_time_fast_fast_plus_mode = 0x02020202, > > + .setup_hold_time_hs_mode = 0x090909, > > + .has_interface_timing_reg = true, }; > > Why tegra194_i2c_hw can't be reused by T234? Looks like I2C h/w hasn't > changed and somebody just made a minor tuning of the timing parameters, does > it really matter in practice? The timing parameters are important to get the desired data rate for I2C. The values, unfortunately, cannot be reused from Tegra194. Thanks, Akhil -- nvpublic
19.01.2022 11:20, Akhil R пишет: >> 13.01.2022 16:30, Akhil R пишет: >>> +static const struct tegra_i2c_hw_feature tegra234_i2c_hw = { >>> + .has_continue_xfer_support = true, >>> + .has_per_pkt_xfer_complete_irq = true, >>> + .clk_divisor_hs_mode = 0x2, >>> + .clk_divisor_std_mode = 0x4f, >>> + .clk_divisor_fast_mode = 0x58, >>> + .clk_divisor_fast_plus_mode = 0x24, >>> + .has_config_load_reg = true, >>> + .has_multi_master_mode = true, >>> + .has_slcg_override_reg = true, >>> + .has_mst_fifo = true, >>> + .quirks = &tegra194_i2c_quirks, >>> + .supports_bus_clear = true, >>> + .has_apb_dma = false, >>> + .tlow_std_mode = 0x8, >>> + .thigh_std_mode = 0x7, >>> + .tlow_fast_fastplus_mode = 0x1, >>> + .thigh_fast_fastplus_mode = 0x1, >>> + .setup_hold_time_std_mode = 0x08080808, >>> + .setup_hold_time_fast_fast_plus_mode = 0x02020202, >>> + .setup_hold_time_hs_mode = 0x090909, >>> + .has_interface_timing_reg = true, }; >> >> Why tegra194_i2c_hw can't be reused by T234? Looks like I2C h/w hasn't >> changed and somebody just made a minor tuning of the timing parameters, does >> it really matter in practice? > The timing parameters are important to get the desired data rate for I2C. The values, > unfortunately, cannot be reused from Tegra194. From where those T194 parameters specified in the Tegra I2C driver came from? I'm now looking at T194 TRM (Xavier_TRM_DP09253002_v1.3p 10.2.3.1.1 Example Settings for Various I2C Speeds) and see that all the values should match T234. Please check whether T194 configuration is correct and fix it if needed.
> >>> +static const struct tegra_i2c_hw_feature tegra234_i2c_hw = { > >>> + .has_continue_xfer_support = true, > >>> + .has_per_pkt_xfer_complete_irq = true, > >>> + .clk_divisor_hs_mode = 0x2, > >>> + .clk_divisor_std_mode = 0x4f, > >>> + .clk_divisor_fast_mode = 0x58, > >>> + .clk_divisor_fast_plus_mode = 0x24, > >>> + .has_config_load_reg = true, > >>> + .has_multi_master_mode = true, > >>> + .has_slcg_override_reg = true, > >>> + .has_mst_fifo = true, > >>> + .quirks = &tegra194_i2c_quirks, > >>> + .supports_bus_clear = true, > >>> + .has_apb_dma = false, > >>> + .tlow_std_mode = 0x8, > >>> + .thigh_std_mode = 0x7, > >>> + .tlow_fast_fastplus_mode = 0x1, > >>> + .thigh_fast_fastplus_mode = 0x1, > >>> + .setup_hold_time_std_mode = 0x08080808, > >>> + .setup_hold_time_fast_fast_plus_mode = 0x02020202, > >>> + .setup_hold_time_hs_mode = 0x090909, > >>> + .has_interface_timing_reg = true, }; > >> > >> Why tegra194_i2c_hw can't be reused by T234? Looks like I2C h/w hasn't > >> changed and somebody just made a minor tuning of the timing parameters, > does > >> it really matter in practice? > > The timing parameters are important to get the desired data rate for I2C. The > values, > > unfortunately, cannot be reused from Tegra194. > > From where those T194 parameters specified in the Tegra I2C driver came > from? > > I'm now looking at T194 TRM (Xavier_TRM_DP09253002_v1.3p 10.2.3.1.1 > Example Settings for Various I2C Speeds) and see that all the values > should match T234. Please check whether T194 configuration is correct > and fix it if needed. Thanks for highlighting this. There are adjustments in the default timing values of T194 from TRM. I am checking if these changes can be used for T234 as well. Will send an updated patch if the same values apply for T234. Thanks, Akhil
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 03cea10..3e8f3f5 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -1614,7 +1614,32 @@ static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { .has_interface_timing_reg = true, }; +static const struct tegra_i2c_hw_feature tegra234_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 0x2, + .clk_divisor_std_mode = 0x4f, + .clk_divisor_fast_mode = 0x58, + .clk_divisor_fast_plus_mode = 0x24, + .has_config_load_reg = true, + .has_multi_master_mode = true, + .has_slcg_override_reg = true, + .has_mst_fifo = true, + .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_fastplus_mode = 0x1, + .thigh_fast_fastplus_mode = 0x1, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_fast_plus_mode = 0x02020202, + .setup_hold_time_hs_mode = 0x090909, + .has_interface_timing_reg = true, +}; + static const struct of_device_id tegra_i2c_of_match[] = { + { .compatible = "nvidia,tegra234-i2c", .data = &tegra234_i2c_hw, }, { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, }, { .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, }, { .compatible = "nvidia,tegra210-i2c-vi", .data = &tegra210_i2c_hw, },
Add Tegra234 specific hw struct and compatible in i2c-tegra driver Signed-off-by: Akhil R <akhilrajeev@nvidia.com> --- drivers/i2c/busses/i2c-tegra.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)