| Message ID | 20200923105206.7988-1-faiz_abbas@ti.com |
|---|---|
| Headers | show |
| Series | Add UHS mode support for TI's AM65x, J721e, J7200 boards | expand |
On 23/09/20 4:22 pm, Faiz Abbas wrote: > With the new SW tuning App note[1], a custom tuning algorithm is > required for eMMC HS200, HS400 and SD card UHS modes. The algorithm > involves running through the 32 possible input tap delay values and > sending the appropriate tuning command (CMD19/21) for each of them > to get a fail or pass result for each of the values. Typically, the > range will have a small contiguous failing window. Considering the > tuning range as a circular buffer, the algorithm then sets a final > tuned value directly opposite to the failing window. > > [1] https://www.ti.com/lit/pdf/spract9 > > Signed-off-by: Faiz Abbas <faiz_abbas@ti.com> Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com> > --- > drivers/mmc/host/sdhci_am654.c | 41 ++++++++++++++++++++++++++++++++++ > 1 file changed, 41 insertions(+) > > diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c > index 1213b711e60a..5af7638ad606 100644 > --- a/drivers/mmc/host/sdhci_am654.c > +++ b/drivers/mmc/host/sdhci_am654.c > @@ -396,7 +396,46 @@ static u32 sdhci_am654_cqhci_irq(struct sdhci_host *host, u32 intmask) > return 0; > } > > +#define ITAP_MAX 32 > +static int sdhci_am654_platform_execute_tuning(struct sdhci_host *host, > + u32 opcode) > +{ > + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); > + struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host); > + int cur_val, prev_val = 1, fail_len = 0, pass_window = 0, pass_len; > + u32 itap; > + > + /* Enable ITAPDLY */ > + regmap_update_bits(sdhci_am654->base, PHY_CTRL4, ITAPDLYENA_MASK, > + 1 << ITAPDLYENA_SHIFT); > + > + for (itap = 0; itap < ITAP_MAX; itap++) { > + sdhci_am654_write_itapdly(sdhci_am654, itap); > + > + cur_val = !mmc_send_tuning(host->mmc, opcode, NULL); > + if (cur_val && !prev_val) > + pass_window = itap; > + > + if (!cur_val) > + fail_len++; > + > + prev_val = cur_val; > + } > + /* > + * Having determined the length of the failing window and start of > + * the passing window calculate the length of the passing window and > + * set the final value halfway through it considering the range as a > + * circular buffer > + */ > + pass_len = ITAP_MAX - fail_len; > + itap = (pass_window + (pass_len >> 1)) % ITAP_MAX; > + sdhci_am654_write_itapdly(sdhci_am654, itap); > + > + return 0; > +} > + > static struct sdhci_ops sdhci_am654_ops = { > + .platform_execute_tuning = sdhci_am654_platform_execute_tuning, > .get_max_clock = sdhci_pltfm_clk_get_max_clock, > .get_timeout_clock = sdhci_pltfm_clk_get_max_clock, > .set_uhs_signaling = sdhci_set_uhs_signaling, > @@ -426,6 +465,7 @@ static const struct sdhci_am654_driver_data sdhci_am654_drvdata = { > }; > > static struct sdhci_ops sdhci_j721e_8bit_ops = { > + .platform_execute_tuning = sdhci_am654_platform_execute_tuning, > .get_max_clock = sdhci_pltfm_clk_get_max_clock, > .get_timeout_clock = sdhci_pltfm_clk_get_max_clock, > .set_uhs_signaling = sdhci_set_uhs_signaling, > @@ -449,6 +489,7 @@ static const struct sdhci_am654_driver_data sdhci_j721e_8bit_drvdata = { > }; > > static struct sdhci_ops sdhci_j721e_4bit_ops = { > + .platform_execute_tuning = sdhci_am654_platform_execute_tuning, > .get_max_clock = sdhci_pltfm_clk_get_max_clock, > .get_timeout_clock = sdhci_pltfm_clk_get_max_clock, > .set_uhs_signaling = sdhci_set_uhs_signaling, >
On Wed, 23 Sep 2020 at 12:52, Faiz Abbas <faiz_abbas@ti.com> wrote: > > The following are driver and documentation patches to enable UHS modes for > TI's AM65x, J721e, and J7200 boards. Device tree and defconfig patches > will be sent in a separate series. > > With the complete set, the following maximum modes will be supported: > > am654x-evm,idk - SDR104, HS200 > j721e-common-proc-board - DDR50, HS200 > j7200-common-proc-board - DDR50, HS200 > > These patches mainly add support for the software tuning algorithm[1] > needed for higher speed modes > > [1] [1] https://www.ti.com/lit/pdf/spract9 > > Faiz Abbas (6): > dt-bindings: mmc: sdhci-am654: Convert sdhci-am654 controller > documentation to json schema > dt-bindings: mmc: sdhci-am654: Add documentation for input tap delay > mmc: sdhci_am654: Fix hard coded otap delay array size > mmc: sdhci_am654: Add support for input tap delay > mmc: sdhci_am654: Add support for software tuning > mmc: sdhci_am654: Enable tuning for SDR50 > > .../devicetree/bindings/mmc/sdhci-am654.txt | 65 ------ > .../devicetree/bindings/mmc/sdhci-am654.yaml | 218 ++++++++++++++++++ > drivers/mmc/host/sdhci_am654.c | 179 ++++++++++---- > 3 files changed, 358 insertions(+), 104 deletions(-) > delete mode 100644 Documentation/devicetree/bindings/mmc/sdhci-am654.txt > create mode 100644 Documentation/devicetree/bindings/mmc/sdhci-am654.yaml > > -- > 2.17.1 > Applied for next, thanks! Kind regards Uffe
The following are driver and documentation patches to enable UHS modes for TI's AM65x, J721e, and J7200 boards. Device tree and defconfig patches will be sent in a separate series. With the complete set, the following maximum modes will be supported: am654x-evm,idk - SDR104, HS200 j721e-common-proc-board - DDR50, HS200 j7200-common-proc-board - DDR50, HS200 These patches mainly add support for the software tuning algorithm[1] needed for higher speed modes [1] [1] https://www.ti.com/lit/pdf/spract9 Faiz Abbas (6): dt-bindings: mmc: sdhci-am654: Convert sdhci-am654 controller documentation to json schema dt-bindings: mmc: sdhci-am654: Add documentation for input tap delay mmc: sdhci_am654: Fix hard coded otap delay array size mmc: sdhci_am654: Add support for input tap delay mmc: sdhci_am654: Add support for software tuning mmc: sdhci_am654: Enable tuning for SDR50 .../devicetree/bindings/mmc/sdhci-am654.txt | 65 ------ .../devicetree/bindings/mmc/sdhci-am654.yaml | 218 ++++++++++++++++++ drivers/mmc/host/sdhci_am654.c | 179 ++++++++++---- 3 files changed, 358 insertions(+), 104 deletions(-) delete mode 100644 Documentation/devicetree/bindings/mmc/sdhci-am654.txt create mode 100644 Documentation/devicetree/bindings/mmc/sdhci-am654.yaml