Merge tag 'soc-drivers-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM SoC driver updates from Arnd Bergmann:
 "As usual, there are lots of minor driver changes across SoC platforms
  from NXP, Amlogic, AMD Zynq, Mediatek, Qualcomm, Apple and Samsung.
  These usually add support for additional chip variations in existing
  drivers, but also add features or bugfixes.

  The SCMI firmware subsystem gains a unified raw userspace interface
  through debugfs, which can be used for validation purposes.

  Newly added drivers include:

   - New power management drivers for StarFive JH7110, Allwinner D1 and
     Renesas RZ/V2M

   - A driver for Qualcomm battery and power supply status

   - A SoC device driver for identifying Nuvoton WPCM450 chips

   - A regulator coupler driver for Mediatek MT81xxv"

* tag 'soc-drivers-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (165 commits)
  power: supply: Introduce Qualcomm PMIC GLINK power supply
  soc: apple: rtkit: Do not copy the reg state structure to the stack
  soc: sunxi: SUN20I_PPU should depend on PM
  memory: renesas-rpc-if: Remove redundant division of dummy
  soc: qcom: socinfo: Add IDs for IPQ5332 and its variant
  dt-bindings: arm: qcom,ids: Add IDs for IPQ5332 and its variant
  dt-bindings: power: qcom,rpmpd: add RPMH_REGULATOR_LEVEL_LOW_SVS_L1
  firmware: qcom_scm: Move qcom_scm.h to include/linux/firmware/qcom/
  MAINTAINERS: Update qcom CPR maintainer entry
  dt-bindings: firmware: document Qualcomm SM8550 SCM
  dt-bindings: firmware: qcom,scm: add qcom,scm-sa8775p compatible
  soc: qcom: socinfo: Add Soc IDs for IPQ8064 and variants
  dt-bindings: arm: qcom,ids: Add Soc IDs for IPQ8064 and variants
  soc: qcom: socinfo: Add support for new field in revision 17
  soc: qcom: smd-rpm: Add IPQ9574 compatible
  soc: qcom: pmic_glink: remove redundant calculation of svid
  soc: qcom: stats: Populate all subsystem debugfs files
  dt-bindings: soc: qcom,rpmh-rsc: Update to allow for generic nodes
  soc: qcom: pmic_glink: add CONFIG_NET/CONFIG_OF dependencies
  soc: qcom: pmic_glink: Introduce altmode support
  ...

1 files changed, 25 insertions, 2 deletions

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 129f68d7a6f5..acd83d29c866 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c
@@ -738,8 +738,31 @@ EXPORT_SYMBOL_GPL(zynqmp_pm_get_pll_frac_data);
  */
 int zynqmp_pm_set_sd_tapdelay(u32 node_id, u32 type, u32 value)
 {
-	return zynqmp_pm_invoke_fn(PM_IOCTL, node_id, IOCTL_SET_SD_TAPDELAY,
-				   type, value, NULL);
+	u32 reg = (type == PM_TAPDELAY_INPUT) ? SD_ITAPDLY : SD_OTAPDLYSEL;
+	u32 mask = (node_id == NODE_SD_0) ? GENMASK(15, 0) : GENMASK(31, 16);
+
+	if (value) {
+		return zynqmp_pm_invoke_fn(PM_IOCTL, node_id,
+					   IOCTL_SET_SD_TAPDELAY,
+					   type, value, NULL);
+	}
+
+	/*
+	 * Work around completely misdesigned firmware API on Xilinx ZynqMP.
+	 * The IOCTL_SET_SD_TAPDELAY firmware call allows the caller to only
+	 * ever set IOU_SLCR SD_ITAPDLY Register SD0_ITAPDLYENA/SD1_ITAPDLYENA
+	 * bits, but there is no matching call to clear those bits. If those
+	 * bits are not cleared, SDMMC tuning may fail.
+	 *
+	 * Luckily, there are PM_MMIO_READ/PM_MMIO_WRITE calls which seem to
+	 * allow complete unrestricted access to all address space, including
+	 * IOU_SLCR SD_ITAPDLY Register and all the other registers, access
+	 * to which was supposed to be protected by the current firmware API.
+	 *
+	 * Use PM_MMIO_READ/PM_MMIO_WRITE to re-implement the missing counter
+	 * part of IOCTL_SET_SD_TAPDELAY which clears SDx_ITAPDLYENA bits.
+	 */
+	return zynqmp_pm_invoke_fn(PM_MMIO_WRITE, reg, mask, 0, 0, NULL);
 }
 EXPORT_SYMBOL_GPL(zynqmp_pm_set_sd_tapdelay);