scsi: ufs: Split the drivers/scsi/ufs directory

Split the drivers/scsi/ufs directory into 'core' and 'host' directories
under the drivers/ufs/ directory. Move shared header files into the
include/ufs/ directory. This separation makes it clear which header files
UFS drivers are allowed to include (include/ufs/*.h) and which header files
UFS drivers are not allowed to include (drivers/ufs/core/*.h).

Update the MAINTAINERS file. Add myself as a UFS reviewer.

Link: https://lore.kernel.org/r/20220511212552.655341-1-bvanassche@acm.org
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Bean Huo <beanhuo@micron.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Keoseong Park <keosung.park@samsung.com>
Tested-by: Bean Huo <beanhuo@micron.com>
Tested-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Acked-by: Avri Altman <avri.altman@wdc.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 116 insertions, 0 deletions

diff --git a/include/ufs/ufs_quirks.h b/include/ufs/ufs_quirks.h
new file mode 100644
index 000000000000..bcb4f004bed5
--- /dev/null
+++ b/include/ufs/ufs_quirks.h
@@ -0,0 +1,116 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2014-2016, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _UFS_QUIRKS_H_
+#define _UFS_QUIRKS_H_
+
+/* return true if s1 is a prefix of s2 */
+#define STR_PRFX_EQUAL(s1, s2) !strncmp(s1, s2, strlen(s1))
+
+#define UFS_ANY_VENDOR 0xFFFF
+#define UFS_ANY_MODEL  "ANY_MODEL"
+
+#define UFS_VENDOR_MICRON      0x12C
+#define UFS_VENDOR_SAMSUNG     0x1CE
+#define UFS_VENDOR_SKHYNIX     0x1AD
+#define UFS_VENDOR_TOSHIBA     0x198
+#define UFS_VENDOR_WDC         0x145
+
+/**
+ * ufs_dev_quirk - ufs device quirk info
+ * @card: ufs card details
+ * @quirk: device quirk
+ */
+struct ufs_dev_quirk {
+	u16 wmanufacturerid;
+	const u8 *model;
+	unsigned int quirk;
+};
+
+/*
+ * Some vendor's UFS device sends back to back NACs for the DL data frames
+ * causing the host controller to raise the DFES error status. Sometimes
+ * such UFS devices send back to back NAC without waiting for new
+ * retransmitted DL frame from the host and in such cases it might be possible
+ * the Host UniPro goes into bad state without raising the DFES error
+ * interrupt. If this happens then all the pending commands would timeout
+ * only after respective SW command (which is generally too large).
+ *
+ * We can workaround such device behaviour like this:
+ * - As soon as SW sees the DL NAC error, it should schedule the error handler
+ * - Error handler would sleep for 50ms to see if there are any fatal errors
+ *   raised by UFS controller.
+ *    - If there are fatal errors then SW does normal error recovery.
+ *    - If there are no fatal errors then SW sends the NOP command to device
+ *      to check if link is alive.
+ *        - If NOP command times out, SW does normal error recovery
+ *        - If NOP command succeed, skip the error handling.
+ *
+ * If DL NAC error is seen multiple times with some vendor's UFS devices then
+ * enable this quirk to initiate quick error recovery and also silence related
+ * error logs to reduce spamming of kernel logs.
+ */
+#define UFS_DEVICE_QUIRK_RECOVERY_FROM_DL_NAC_ERRORS (1 << 2)
+
+/*
+ * Few Toshiba UFS device models advertise RX_MIN_ACTIVATETIME_CAPABILITY as
+ * 600us which may not be enough for reliable hibern8 exit hardware sequence
+ * from UFS device.
+ * To workaround this issue, host should set its PA_TACTIVATE time to 1ms even
+ * if device advertises RX_MIN_ACTIVATETIME_CAPABILITY less than 1ms.
+ */
+#define UFS_DEVICE_QUIRK_PA_TACTIVATE	(1 << 4)
+
+/*
+ * It seems some UFS devices may keep drawing more than sleep current
+ * (atleast for 500us) from UFS rails (especially from VCCQ rail).
+ * To avoid this situation, add 2ms delay before putting these UFS
+ * rails in LPM mode.
+ */
+#define UFS_DEVICE_QUIRK_DELAY_BEFORE_LPM	(1 << 6)
+
+/*
+ * Some UFS devices require host PA_TACTIVATE to be lower than device
+ * PA_TACTIVATE, enabling this quirk ensure this.
+ */
+#define UFS_DEVICE_QUIRK_HOST_PA_TACTIVATE	(1 << 7)
+
+/*
+ * The max. value PA_SaveConfigTime is 250 (10us) but this is not enough for
+ * some vendors.
+ * Gear switch from PWM to HS may fail even with this max. PA_SaveConfigTime.
+ * Gear switch can be issued by host controller as an error recovery and any
+ * software delay will not help on this case so we need to increase
+ * PA_SaveConfigTime to >32us as per vendor recommendation.
+ */
+#define UFS_DEVICE_QUIRK_HOST_PA_SAVECONFIGTIME	(1 << 8)
+
+/*
+ * Some UFS devices require VS_DebugSaveConfigTime is 0x10,
+ * enabling this quirk ensure this.
+ */
+#define UFS_DEVICE_QUIRK_HOST_VS_DEBUGSAVECONFIGTIME	(1 << 9)
+
+/*
+ * Some pre-3.1 UFS devices can support extended features by upgrading
+ * the firmware. Enable this quirk to make UFS core driver probe and enable
+ * supported features on such devices.
+ */
+#define UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES (1 << 10)
+
+/*
+ * Some UFS devices require delay after VCC power rail is turned-off.
+ * Enable this quirk to introduce 5ms delays after VCC power-off during
+ * suspend flow.
+ */
+#define UFS_DEVICE_QUIRK_DELAY_AFTER_LPM        (1 << 11)
+
+/*
+ * Some UFS devices require L2P entry should be swapped before being sent to the
+ * UFS device for HPB READ command.
+ */
+#define UFS_DEVICE_QUIRK_SWAP_L2P_ENTRY_FOR_HPB_READ (1 << 12)
+
+#endif /* UFS_QUIRKS_H_ */