[PATCH V20 00/22] Add support UHS-II for GL9755 and GL9767

Victor Shih
2024-09-05T10:20:10Z

Summary
=======
These patches[1] support UHS-II and fix GL9755 and GL9767
UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755
patch#22: for GL9767

Tests
=====
Ran 'dd' command to evaluate the performance 3 times:
(SanDisk UHS-II card on GL9755 controller)
Read Write
UHS-II disabled (UHS-I): 84.5MB/s 54.1MB/s
UHS-II enabled : 190MB/s 74.4MB/s
Read Write
UHS-II disabled (UHS-I): 85.4MB/s 56.2MB/s
UHS-II enabled : 169MB/s 75.2MB/s
Read Write
UHS-II disabled (UHS-I): 83.3MB/s 54.2MB/s
UHS-II enabled : 187MB/s 77.1MB/s
(SanDisk UHS-II card on GL9767 controller)
Read Write
UHS-II disabled (UHS-I): 84.9MB/s 56.5MB/s
UHS-II enabled : 189MB/s 76.4MB/s
Read Write
UHS-II disabled (UHS-I): 85.2MB/s 48.5MB/s
UHS-II enabled : 209MB/s 75.4MB/s
Read Write
UHS-II disabled (UHS-I): 85.6MB/s 50.2MB/s
UHS-II enabled : 185MB/s 78.3MB/s

Test command
=====
Read: dd if=/dev/mmcxxx of=/dev/null bs=4096k count=2000 iflag=direct
Write:dd if=/dev/zero of=/dev/mmcxxx bs=4096k count=2000 oflag=direct

Changes in v20 (September. 05, 2024)
* Rebase on latest mmc/next.
* Patch#21: Remove sdhci_gli_enable_internal_clock functon
unused clk_ctrl variable.
Make a function sdhci_gli_wait_software_reset_done()
for gl9755 reset.
* Patch#22: Use the function sdhci_gli_wait_software_reset_done()
for gl9767 reset.

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20240829101539.5058-1-victorshihgli@gmail.com/

----------------- original cover letter from v19 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 and GL9767
UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755
patch#22: for GL9767

Tests
=====
Ran 'dd' command to evaluate the performance:
(SanDisk UHS-II card on GL9755 controller)
Read Write
UHS-II disabled (UHS-I): 84.8MB/s 53.6MB/s
UHS-II enabled : 183MB/s 90.8MB/s
(SanDisk UHS-II card on GL9767 controller)
Read Write
UHS-II disabled (UHS-I): 83.3MB/s 51.6MB/s
UHS-II enabled : 202MB/s 73.3MB/s

Changes in v19 (August. 29, 2024)
* Rebase on latest mmc/next.
* Patch#16: cmd->uhs2_cmd->uhs2_resp is always true, remove it from
safety check in the __sdhci_uhs2_finish_command().
* Patch#17: Corrected sdhci_uhs2_reset() parameter errors
in the sdhci_uhs2_request_done().
* Patch#21: Add sdhci_gli_enable_internal_clock() to simplify the code
in the sdhci_gl9755_reset().
* Patch#22: Use sdhci_gli_enable_internal_clock() to simplify the code
in the sdhci_gl9767_reset().
Directly reading the SDHCI_PRESENT_STATE register to replace
the get_cd() avoids the possibility of the get_cd() sleeping
in the sdhci_gl9767_set_card_detect_debounce_time().
Refine the position of gli_set_9767() in the
sdhci_gl9767_reset().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20240802102229.10204-1-victorshihgli@gmail.com/

----------------- original cover letter from v18 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 and GL9767
UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755
patch#22: for GL9767

Tests
=====
Ran 'dd' command to evaluate the performance:
(SanDisk UHS-II card on GL9755 controller)
Read Write
UHS-II disabled (UHS-I): 83.9MB/s 48.6MB/s
UHS-II enabled : 199MB/s 74.3MB/s
(SanDisk UHS-II card on GL9767 controller)
Read Write
UHS-II disabled (UHS-I): 83.6MB/s 50.1MB/s
UHS-II enabled : 183MB/s 77.8MB/s

Changes in v18 (August. 02, 2024)
* Rebase on latest mmc/next.
* Patch#17: Modify the judgment condition in sdhci_uhs2_reset_cmd_data()
and replace it from mmc_card_uhs2()
to host->mmc->uhs2_sd_tran flag.
* Patch#22: Add new register settings for gl9767.
Add card_event in the sdhci_ops for gl9767.
Add sdhci_gl9767_set_card_detect_debounce_time()
to configure the gl9767.
Adjust the sdhci_gl9767_reset() process for gl9767.

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20240620104444.5862-1-victorshihgli@gmail.com/

----------------- original cover letter from v17 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 and GL9767
UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755
patch#22: for GL9767

Changes in v17 (June. 20, 2024)
* Rebase on latest mmc/next.
* Drop patch#8 of uhs2 patches series v16.
* Patch#11: Move the sdhci_uhs2_reset_cmd_data() to the other patch
it was used for the first time.
* Patch#12: Export sdhci_uhs2_set_power() function.
* Patch#16: Add new parameter to __sdhci_finish_data_common().
* Patch#17: Add sdhci_uhs2_reset_cmd_data() and sdhci_uhs2_needs_reset() to
resolve the data error or cmd error.
* Patch#21: Rname gl9755_overcurrent_event_enable() to
sdhci_gli_overcurrent_event_enable().
* Patch#22: Use mmc_card_uhs2() to simplify the code in the
sdhci_gl9767_reset().
Use mmc_card_uhs2() to simplify the code in the
sdhci_gl9767_set_power().
Add sdhci_gli_overcurrent_event_enable() to
sdhci_gl9767_set_power().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20240522110909.10060-1-victorshihgli@gmail.com/

----------------- original cover letter from v16 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 and GL9767
UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#8: for core
patch#9-#21: for sdhci
patch#22: for GL9755
patch#23: for GL9767

Changes in v16 (May. 22, 2024)
* rebased to the linux-kernel-v6.9.0-rc2 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V14 00/21] Add support UHS-II for GL9755.
* Patch#8: Separate the Error Recovery mechanism from patch#7 to patch#8.
* Patch#16: Remove irrelevant definition in the sdhci_calc_timeout_uhs2().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20240123062827.8525-1-victorshihgli@gmail.com/

----------------- original cover letter from v15 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 and GL9767
UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755
patch#22: for GL9767

Changes in v15 (April. 22, 2024)
* rebased to the linux-kernel-v6.9.0-rc2 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V14 00/21] Add support UHS-II for GL9755.
* Patch#07: Move struct uhs2_command uhs2_cmd to struct mmc_request and
modify whatever other changers to make it work.
Refer the SD Host Controller Standard Specification
Section 3.10 to add Error Recovery mechanism to recover
the command error.
* Patch#11: Refer the SD Host Controller Standard Specification
Section 3.10 to add reset command data mechanism.
* Patch#15: Resolve merge conflicts and reduce unnecessary line breaks.
* Patch#16: Adjust the parameters used in the __sdhci_uhs2_finish_command()
to match changes in the Patch#7.
* Patch#21: Adjust gl9755_vendor_init() to the correct function.
* Patch#22: Add gl9767 to support uhs2 function.

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20240123062827.8525-1-victorshihgli@gmail.com/

----------------- original cover letter from v14 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755

Changes in v14 (January. 23, 2024)
* rebased to the linux-kernel-v6.7.0-rc4 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V13 00/21] Add support UHS-II for GL9755.
* Patch#03: Move mmc_card_uhs2() to include/linux/mmc/host.h, so that
mmc_card_uhs2() can be available for host drivers.
* Patch#10: Use mmc_card_uhs2() to stead sdhci_uhs2_mode() in the
sdhci_uhs2_dump_regs().
* Patch#11: Since mmc_card_uhs2() is the same as sdhci_uhs2_mode(), so
drop sdhci_uhs2_mode() and use mmc_card_uhs2() instead of
sdhci_uhs2_mode().
* Patch#13: Use mmc_card_uhs2() to stead sdhci_uhs2_mode() in the
sdhci_uhs2_set_timeout().
* Patch#14: Use mmc_card_uhs2() to stead sdhci_uhs2_mode() in the
sdhci_uhs2_set_ios().
* Patch#16: Use mmc_card_uhs2() to stead sdhci_uhs2_mode() in the
sdhci_uhs2_request().
* Patch#17: Use mmc_card_uhs2() to stead sdhci_uhs2_mode() in the
sdhci_uhs2_complete_work(), sdhci_uhs2_irq() and
sdhci_uhs2_thread_irq().
* Patch#18: Use mmc_card_uhs2() to stead sdhci_uhs2_mode() in the
__sdhci_uhs2_remove_host().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230915094351.11120-1-victorshihgli@gmail.com/

----------------- original cover letter from v13 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#20: for sdhci
patch#21: for GL9755

Changes in v13 (November. 17, 2023)
* rebased to the linux-kernel-v6.7.0-rc1 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V12 00/23] Add support UHS-II for GL9755.
* according to the comments provided by Ulf Hansson to modify the
patches base on the [V12 00/23] Add support UHS-II for GL9755.
* Add new patch#6 to re-factoring the code.
* Patch#7: Separate __mmc_go_idle() into one patch for re-factorring the code.
Move mmc_decode_scr declaration to sd.h.
Ues uhs2_sd_tran to stead MMC_UHS2_SD_TRAN.
Drop unnecessary comment.
* Patch#11: Use ios timing to stead MMC_UHS2_SUPPORT for indicate the UHS2 mode.
* Patch#12: Drop use vmmc2.
Modify comment message.
* Patch#13: Modify comment message.
* Patch#14: Add judgment condition for power mode in the __sdhci_uhs2_set_ios().
Modify comment message.
* Patch#15: Merge Patch#15, Patch#16 and Patch#17 of v12 version into Patch#15 in v13 version.
Use definitions to simplify code.
Modify comment message.
* Patch#16: Re-order function to avoid declaration.
Remove unnecessary function.
* Patch#17: Re-order function to avoid declaration.
Remove unnecessary definitions.
* Patch#18: Re-order function to avoid declaration.
Use vqmmc2 to stead vmmc2.
* Patch#21: Ues uhs2_sd_tran to stead MMC_UHS2_SD_TRAN.

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230915094351.11120-1-victorshihgli@gmail.com/

----------------- original cover letter from v12 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#22: for sdhci
patch#23: for GL9755

Changes in v12 (September. 15, 2023)
* rebased to the linux-kernel-v6.6.0-rc1 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V11 00/23] Add support UHS-II for GL9755.
* according to the comments provided by Ulf Hansson to modify the
patches base on the [V11 00/23] Add support UHS-II for GL9755.
* Patch#5: Remove unused max_current_180_vdd2.
* Patch#6: Use mmc_op_multi() to check DCMD which supports multi
read/write in mmc_uhs2_prepare_cmd().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230908095330.12075-1-victorshihgli@gmail.com/

----------------- original cover letter from v11 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#22: for sdhci
patch#23: for GL9755

Changes in v11 (September. 08, 2023)
* rebased to the linux-kernel-v6.5.0-rc5 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V10 00/23] Add support UHS-II for GL9755.
* Patch#18: Drop the check mmc_card_uhs2_hd_mode(host->mmc)
in sdhci_uhs2_set_transfer_mode().
* Patch#20: Remove unused ocr_avail_uhs2.

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230721101349.12387-1-victorshihgli@gmail.com/

----------------- original cover letter from v10 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#22: for sdhci
patch#23: for GL9755

Changes in v10 (August. 18, 2023)
* rebased to the linux-kernel-v6.5.0-rc5 in Ulf Hansson next branch.
* according to the comments provided by Ulf Hansson to modify the
patches base on the [V9 00/23] Add support UHS-II for GL9755.
* Patch#2: Drop unnecessary definitions and code.
* Patch#3: Modify the commit message.
* Patch#4: Modify the commit message.
* Patch#5: Drop unnecessary definitions.
* Patch#6: Move some definitions of PatchV9[02/23] to PatchV10[06/23].
Move some definitions of PatchV9[05/23] to PatchV10[06/23].
Drop do_multi in the mmc_blk_rw_rq_prep().
Use tmode_half_duplex to instead of uhs2_tmode0_flag.
Move entire control of the tmode into mmc_uhs2_prepare_cmd().
* Patch#11: Move some definitions of PatchV9[05/23] to PatchV10[11/23].
* Patch#18: Use tmode_half_duplex to instead of uhs2_tmode0_flag
in sdhci_uhs2_set_transfer_mode().
* Patch#20: Move some definitions of PatchV9[05/23] to PatchV10[20/23].

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230721101349.12387-1-victorshihgli@gmail.com/

----------------- original cover letter from v9 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#22: for sdhci
patch#23: for GL9755

Changes in v9 (July. 21, 2023)
* rebased to the linux-kernel-v6.5.0-rc1 in Ulf Hansson next branch.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V8 00/23] Add support UHS-II for GL9755.
* Patch#2: move sd_uhs2_operation definition of PatchV8[05/23]
to PatchV9[02/23] for avoid compilation errors.
move uhs2_control definition of PatchV8[05/23]
to PatchV9[02/23] for avoid compilation errors.
move mmc_host flags definition of PatchV8[05/23]
to PatchV9[02/23] for avoid compilation errors.
move mmc_host flags MMC_UHS2_SUPPORT definition of
PatchV8[05/23] to PatchV9[02/23] for avoid compilation errors.
move mmc_host flags MMC_UHS2_SD_TRAN definition of
PatchV8[05/23] to PatchV9[02/23] for avoid compilation errors.
* Patch#7: Modify the commit message.
* Patch#8: Modify the commit message.
* Patch#11: Modify annotations in sdhci_get_vdd_value().
* Patch#14: Simplity the turning_on_clk in sdhci_set_ios().
* Patch#18: Modify the annotations in __sdhci_uhs2_send_command().
* Patch#19: Cancel export state of sdhci_set_mrq_done() function.
* Patch#23: Rename gl9755_pre_detect_init() to sdhci_gli_pre_detect_init().
Rename gl9755_uhs2_reset_sd_tran() to
sdhci_gli_uhs2_reset_sd_tran().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230621100151.6329-1-victorshihgli@gmail.com/

----------------- original cover letter from v8 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup
Sequence[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence
[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include
Section 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II
Setting Register Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy
SD compatibility and preserve Legacy SD infrastructures (Section 7.1.1
Packet Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#22: for sdhci
patch#23: for GL9755

Changes in v8 (June. 21, 2023)
* rebased to the linux-kernel-v6.4.0-rc6 in Ulf Hansson next branch.
* fix most of checkpatch warnings/errors.
* according to the comments provided by Adrian Hunter to modify the
patches base on the [V7 00/23] Add support UHS-II for GL9755.
* Patch#6: Add MMC_UHS2_SUPPORT to be cleared in sd_uhs2_detect().
Modify return value in sd_uhs2_attach().
* Patch#7: Use tabs instead of spaces.
* Patch#8: Modify MODULE_LICENSE from "GPL v2" to "GPL".
* Patch#10: Adjust the position of matching brackets.
* Patch#11: Adjust the position of matching brackets.
Add the initial value of the pwr in sdhci_uhs2_set_power().
* Patch#13: Initialization be combined with declaration and realigned
in sdhci_calc_timeout_uhs2().
Forward declare struct mmc_command in sdhci_uhs2.h.
* Patch#14: Add the judgment formula for MMC_TIMING_SPEED_A_HD,
MMC_TIMING_SPEED_B and MMC_TIMING_SPEED_B_HD in
__sdhci_uhs2_set_ios().
Add the switch case for MMC_TIMING_SPEED_A_HD,
MMC_TIMING_SPEED_B and MMC_TIMING_SPEED_B_HD in
sdhci_get_preset_value().
mmc_opt_regulator_set_ocr() to instead of
mmc_regulator_set_ocr() in sdhci_uhs2_set_ios().
* Patch#15: usleep_range() to instead of udelay() in
sdhci_uhs2_interface_detect().
read_poll_timeout() to instead of read_poll_timeout_atomic()
in sdhci_uhs2_interface_detect().
Modify return value in sdhci_uhs2_do_detect_init().
* Patch#16: Remove unnecessary include file.
read_poll_timeout() to instead of read_poll_timeout_atomic()
in sdhci_uhs2_enable_clk().
Put the comment on the end and put the lines in descending
line length in sdhci_uhs2_enable_clk().
Modify return value in sdhci_uhs2_enable_clk().
* Patch#17: Reorder the definitions and lose the parentheses in
sdhci_uhs2_set_config().
read_poll_timeout() to instead of read_poll_timeout_atomic()
in sdhci_uhs2_check_dormant().
* Patch#18: Adjust the position of matching brackets in
sdhci_uhs2_send_command_retry().
Modify CameCase definition in __sdhci_uhs2_finish_command().
Modify error message in __sdhci_uhs2_finish_command().
sdhci_uhs2_send_command_retry() to instead of
sdhci_uhs2_send_command() in sdhci_uhs2_request().
Use sdhci_uhs2_mode() to simplify code in
sdhci_uhs2_request_atomic().
Add forward declaration for sdhci_send_command().
* Patch#19: Forward declare struct mmc_request in sdhci_uhs2.h.
Remove forward declaration of sdhci_send_command().
Use mmc_dev() to simplify code in sdhci_request_done_dma().
* Patch#20: Change return type to void for __sdhci_uhs2_add_host_v4().
Remove unused variables in __sdhci_uhs2_add_host_v4().
* Patch#22: Add config select MMC_SDHCI_UHS2 in Kconfig.
* Patch#23: Use sdhci_get_vdd_value() to simplify code in
gl9755_set_power().
Use read_poll_timeout_atomic() to simplify code in
sdhci_wait_clock_stable().
Use read_poll_timeout_atomic() to simplify code in
sdhci_gl9755_reset().

Reference
=========
[1] https://gitlab.com/VictorShih/linux-uhs2.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20230331105546.13607-1-victor.shih@genesyslogic.com.tw/

----------------- original cover letter from v7 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup Sequence
[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include Section
3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II Setting Register
Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy SD
compatibility and preserve Legacy SD infrastructures (Section 7.1.1 Packet
Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#22: for sdhci
patch#23: for GL9755

Changes in v7 (Mar. 31, 2023)
* rebased to the linux-kernel-v6.3.0-rc3 in Ulf Hansson next branch.
* according to the guidance and overall architecture provided
by Ulf Hansson, Ben Chuang and Jason Lai to implement the
UHS-2 Core function based on the patches of the [V4,0/6]
Preparations to support SD UHS-II cards[5].
* according to the guidance and comments provided by
Adrian Hunter, Ben Chuang and AKASHI Takahiro to implement
the UHS-2 Host function based on the patches of the
[RFC,v3.1,00/27] Add support UHS-II for GL9755[4].
* implement the necessary function to let the UHS-2 Core/Host
work properly.
* fix most of checkpatch warnings/errors.
* according to the guidance and comments provided by
Adrian Hunter, Ben Chuang to implement the UHS-2
Host function based on the patches of the
[V5,00/26] Add support UHS-II for GL9755[6].
* according to the guidance and comments provided by
Ulf Hanssion, Adrian Hunter, Ben Chuang to implement the UHS-2
Host function based on the patches of the
[V6,00/24] Add support UHS-II for GL9755[7].
* The uhs2_post_attach_sd() function is no longer needed so drop
the V6 version of the Patch#22.
* Modifies the usage of the flags used by the sdhci host for
MMC_UHS2_INITIALIZED.
* Patch#1: Drop unnecessary bracket.
* Patch#2: Drop sd_uhs2_set_ios function.
Used ->uhs2_control() callback for uhs2_set_ios
in sd_uhs2_power_up().
Used ->uhs2_control() callback for uhs2_set_ios
in sd_uhs2_power_off().
Drop MMC_TIMING_SD_UHS2 in favor of MMC_TIMING_UHS2_SPEED_A.
Modify sd_uhs2_legacy_init to avoid the
sd_uhs2_reinit cycle issue.
* Patch#5: Drop unnecessary definitions.
* Patch#6: Drop unnecessary function.
Drop uhs2_state in favor of ios->timing.
* Patch#7: Reorder values and positions of definitions.
* Patch#9: Used sdhci_uhs2_mode function to simplify.
* Patch#11: Drop pwr variable in sdhci_uhs2_set_power function.
* Patch#14: Modify some descriptions.
Drop unnecessary function.
* Patch#15: Drop using uhs2_reset ops and use sdhci_uhs2_reset function
in the sdhci_do_detect_init function.
* Patch#17: Drop unnecessary function.
* Patch#18: Drop unnecessary whitespace changes.
Cancel the export state of some functions.
* Patch#19: Drop unnecessary function.
Used sdhci_uhs2_mode function to simplify.
Modify some descriptions.
Cancel the export state of some functions.
* Patch#20: Drop using __sdhci_uhs2_host function and use
__sdhci_add_host function in sdhci_uhs2_add_host function.
Cancel the export state of some functions.
* Patch#23: Drop using uhs2_post_attach_sd function.

Reference
=========
[1] https://gitlab.com/ben.chuang/linux-uhs2-gl9755.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20201106022726.19831-1-takahiro.akashi@linaro.org/
[5] https://patchwork.kernel.org/project/linux-mmc/cover/20220418115833.10738-1-jasonlai.genesyslogic@gmail.com/
[6] https://patchwork.kernel.org/project/linux-mmc/cover/20221019110647.11076-1-victor.shih@genesyslogic.com.tw/
[7] https://patchwork.kernel.org/project/linux-mmc/cover/20221213090047.3805-1-victor.shih@genesyslogic.com.tw/

----------------- original cover letter from v6 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup Sequence
[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include Section
3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II Setting Register
Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy SD
compatibility and preserve Legacy SD infrastructures (Section 7.1.1 Packet
Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#23: for sdhci
patch#24: for GL9755

Changes in v6 (Dec. 12, 2022)
* rebased to the linux-kernel-v6.1.0-rc8 in Ulf Hansson next branch.
* according to the guidance and overall architecture provided
by Ulf Hansson, Ben Chuang and Jason Lai to implement the
UHS-2 Core function based on the patches of the [V4,0/6]
Preparations to support SD UHS-II cards[5].
* according to the guidance and comments provided by
Adrian Hunter, Ben Chuang and AKASHI Takahiro to implement
the UHS-2 Host function based on the patches of the
[RFC,v3.1,00/27] Add support UHS-II for GL9755[4].
* implement the necessary function to let the UHS-2 Core/Host
work properly.
* fix most of checkpatch warnings/errors.
* according to the guidance and comments provided by
Adrian Hunter, Ben Chuang to implement the UHS-2
Host function based on the patches of the
[V5,00/26] Add support UHS-II for GL9755[6].
* The uhs2_post_attach_sd() has implemented in Patch#6 and
Patch#17 so drop the V5 version of the Patch#23.
* Modifies the usage of the flags used by the sdhci host for
MMC_UHS2_INITIALIZED.
* Patch#5: Drop unused definitions and functions.
* Patch#7: Rename definitions.
Use BIT() GENMASK() in some cases.
* Patch#8: Merge V5 version of Patch[7] and Patch[9] into
V6 version of Patch[8].
* Patch#9: Drop unnecessary function.
Rename used definitions.
* Patch#10: Drop unnecessary function and simplify some code.
* Patch#11: Drop unnecessary function.
Add new mmc_opt_regulator_set_ocr function.
* Patch#13: Drop unnecessary function.
Use GENMASK() and FIELD_PREP() in some cases.
* Patch#14: Drop unnecessary function.
Modify return value in some function.
Use GENMASK() and FIELD_PREP() in some cases.
* Patch#15: Drop unnecessary function.
Rename used definitions.
Use GENMASK() and FIELD_GET() in some cases.
Wrap at 100 columns in some functions.
* Patch#16: Drop unnecessary function.
* Patch#17: Drop unnecessary function.
Drop the unnecessary parameter when call the DBG()
function.
Rename used definitions.
Cancel the export state of some functions.
Use GENMASK() and FIELD_PREP() in some cases.
* Patch#18: Drop unnecessary function.
Add uhs2_dev_cmd function to simplify some functions.
Rename used definitions.
Cancel the export state of some functions.
Use GENMASK() and FIELD_PREP() in some cases.
* Patch#19: Drop unnecessary function.
Add sdhci_uhs2_mode() in some functions.
Rename used definitions.
Cancel the export state of some functions.
* Patch#20: Add new complete_work_fn/thread_irq_fn variables in
struct sdhci_host.
Use complete_work_fn/thread_irq_fn variables in
sdhci_alloc_host()/sdhci_uhs2_add_host().
Rename used definitions.
* Patch[24]: Rename used definitions.

Reference
=========
[1] https://gitlab.com/ben.chuang/linux-uhs2-gl9755.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20201106022726.19831-1-takahiro.akashi@linaro.org/
[5] https://patchwork.kernel.org/project/linux-mmc/cover/20220418115833.10738-1-jasonlai.genesyslogic@gmail.com/
[6] https://patchwork.kernel.org/project/linux-mmc/cover/20221019110647.11076-1-victor.shih@genesyslogic.com.tw/

----------------- original cover letter from v5 -----------------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup Sequence
[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include Section
3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II Setting Register
Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy SD
compatibility and preserve Legacy SD infrastructures (Section 7.1.1 Packet
Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#6: for core
patch#7-#25: for sdhci
patch#26: for GL9755

Changes in v5 (Oct. 19, 2022)
* rebased to the linux-kernel-v6.1-rc1 in Ulf Hansson next branch.
* according to the guidance and overall architecture provided
by Ulf Hansson, Ben Chuang and Jason Lai to implement the
UHS-2 Core function based on the patches of the [V4,0/6]
Preparations to support SD UHS-II cards[5].
* according to the guidance and comments provided by
Adrian Hunter, Ben Chuang and AKASHI Takahiro to implement
the UHS-2 Host function based on the patches of the
[RFC,v3.1,00/27] Add support UHS-II for GL9755[4].
* implement the necessary function to let the UHS-2 Core/Host
work properly.
* fix most of checkpatch warnings/errors

Reference
=========
[1] https://gitlab.com/ben.chuang/linux-uhs2-gl9755.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02
[4] https://patchwork.kernel.org/project/linux-mmc/cover/20201106022726.19831-1-takahiro.akashi@linaro.org/
[5] https://patchwork.kernel.org/project/linux-mmc/cover/20220418115833.10738-1-jasonlai.genesyslogic@gmail.com/

----------------- original cover letter from v3.1 -----------------
This is an interim snapshot of our next version, v4, for enabling
UHS-II on MMC/SD.

It is focused on 'sdhci' side to address Adrian's comments regarding
"modularising" sdhci-uhs2.c.
The whole aim of this version is to get early feedback from Adrian (and
others) on this issue. Without any consensus about the code structure,
it would make little sense to go further ahead on sdhci side.
(Actually, Adrian has made no comments other than "modularising" so far.)

I heavily reworked/refactored sdhci-uhs2.c and re-organised the patch
set to meet what I believe Adrian expects; no UHS-II related code in
Legacy (UHS-I) code or sdhci.c.

Nevertheless, almost of all changes I made are trivial and straightforward
in this direction, and I believe that there is no logic changed since v3
except sdhci_uhs2_irq(), as ops->irq hook, where we must deal with UHS-II
command sequences in addition to UHS-II errors. So I added extra handlings.

I admit that there is plenty of room for improvements (for example,
handling host->flags), but again the focal point here is how sdhci-uhs2.c
should be built as a module.

Please review this series (particularly Patch#8-#26 and #27) from this
viewpoint in the first place.
(Ben is working on 'host' side but there is no change on 'host' side
in this submission except a minor tweak.)

Thanks,
-Takahiro Akashi

------ original cover letter from v3 ------
Summary
=======
These patches[1] support UHS-II and fix GL9755 UHS-II compatibility.

About UHS-II, roughly deal with the following three parts:
1) A UHS-II detection and initialization:
- Host setup to support UHS-II (Section 3.13.1 Host Controller Setup Sequence
[2]).
- Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence[2]).
- In step(9) of Section 3.13.2 in [2], UHS-II initialization is include Section
3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II Setting Register
Setup Sequence.

2) Send Legacy SD command through SD-TRAN
- Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy SD
compatibility and preserve Legacy SD infrastructures (Section 7.1.1 Packet
Types and Format Overview[3]).
- Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II
CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]).

3) UHS-II Interrupt
- Except for UHS-II error interrupts, most interrupts share the original
interrupt registers.

Patch structure
===============
patch#1-#7: for core
patch#8-#17: for sdhci
patch#18-#21: for GL9755

Tests
=====
Ran 'dd' command to evaluate the performance:
(SanDisk UHS-II card on GL9755 controller)
Read Write
UHS-II disabled (UHS-I): 88.3MB/s 60.7MB/s
UHS-II enabled : 206MB/s 80MB/s

TODO
====
- replace some define with BIT macro

Reference
=========
[1] https://gitlab.com/ben.chuang/linux-uhs2-gl9755.git
[2] SD Host Controller Simplified Specification 4.20
[3] UHS-II Simplified Addendum 1.02

Changes in v3 (Jul. 10, 2020)
* rebased to v5.8-rc4
* add copyright notice
* reorganize the patch set and split some commits into smaller ones
* separate uhs-2 headers from others
* correct wrong spellings
* fix most of checkpatch warnings/errors
* remove all k[cz]alloc() from the code
* guard sdhci-uhs2 specific code with
'if (IS_ENABLED(CONFIG_MMC_SDHCI_UHS2))'
* make sdhci-uhs2.c as a module
* trivial changes, including
- rename back sdhci-core.c to sdhci.c
- allow vendor code to disable uhs2 if v4_mode == 0
in __sdhci_add_host()
- merge uhs2_power_up() into mmc_power_up()
- remove flag_uhs2 from mmc_attach_sd()
- add function descriptions to EXPORT'ed functions
- other minor code optimization

Changes in v2 (Jan. 9, 2020)
* rebased to v5.5-rc5

Ben Chuang (1):
mmc: sdhci-uhs2: add pre-detect_init hook

Ulf Hansson (4):
mmc: core: Cleanup printing of speed mode at card insertion
mmc: core: Prepare to support SD UHS-II cards
mmc: core: Announce successful insertion of an SD UHS-II card
mmc: core: Extend support for mmc regulators with a vqmmc2

Victor Shih (17):
mmc: core: Add definitions for SD UHS-II cards
mmc: core: Add New function to re-factoring the code
mmc: core: Support UHS-II card control and access
mmc: sdhci: add UHS-II related definitions in headers
mmc: sdhci: add UHS-II module and add a kernel configuration
mmc: sdhci-uhs2: dump UHS-II registers
mmc: sdhci-uhs2: add reset function
mmc: sdhci-uhs2: add set_power() to support vdd2
mmc: sdhci-uhs2: add set_timeout()
mmc: sdhci-uhs2: add set_ios()
mmc: sdhci-uhs2: add uhs2_control() to initialise the interface
mmc: sdhci-uhs2: add request() and others
mmc: sdhci-uhs2: add irq() and others
mmc: sdhci-uhs2: add add_host() and others to set up the driver
mmc: sdhci-pci: add UHS-II support framework
mmc: sdhci-pci-gli: enable UHS-II mode for GL9755
mmc: sdhci-pci-gli: enable UHS-II mode for GL9767

drivers/mmc/core/Makefile | 2 +-
drivers/mmc/core/bus.c | 38 +-
drivers/mmc/core/core.c | 23 +-
drivers/mmc/core/core.h | 1 +
drivers/mmc/core/mmc_ops.c | 24 +-
drivers/mmc/core/mmc_ops.h | 1 +
drivers/mmc/core/regulator.c | 34 +
drivers/mmc/core/sd.c | 10 +-
drivers/mmc/core/sd.h | 5 +
drivers/mmc/core/sd_ops.c | 9 +
drivers/mmc/core/sd_ops.h | 13 +
drivers/mmc/core/sd_uhs2.c | 1326 +++++++++++++++++++++++++++++
drivers/mmc/host/Kconfig | 10 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-pci-core.c | 16 +-
drivers/mmc/host/sdhci-pci-gli.c | 439 +++++++++-
drivers/mmc/host/sdhci-pci.h | 3 +
drivers/mmc/host/sdhci-uhs2.c | 1273 +++++++++++++++++++++++++++
drivers/mmc/host/sdhci-uhs2.h | 190 +++++
drivers/mmc/host/sdhci.c | 281 +++---
drivers/mmc/host/sdhci.h | 75 +-
include/linux/mmc/card.h | 36 +
include/linux/mmc/core.h | 17 +
include/linux/mmc/host.h | 80 ++
include/linux/mmc/sd_uhs2.h | 240 ++++++
25 files changed, 3998 insertions(+), 149 deletions(-)
create mode 100644 drivers/mmc/core/sd_uhs2.c
create mode 100644 drivers/mmc/host/sdhci-uhs2.c
create mode 100644 drivers/mmc/host/sdhci-uhs2.h
create mode 100644 include/linux/mmc/sd_uhs2.h

--
2.25.1