On Fri, Jul 17, 2020 at 6:18 PM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > > On Fri, 10 Jul 2020 at 13:07, Ben Chuang <benchuanggli@xxxxxxxxx> wrote: > > > > Summary > > ======= > > These patches[1] support UHS-II and fix GL9755 UHS-II compatibility. > > First of all, thanks for posting this - and my apologies for not > having the bandwidth to review the earlier versions. > > > > > 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. > > The above points to some specifications, which is good, but what I > really need to be able to do a proper review - is an explanation of > *what*, *why* and *how* the series implements the UHS-II support. What: 1. detect UHS-II interface of a card 2. change card to UHS-II mode 3. send SD command through SD-TRAN 4. go back to legacy interface if not detect UHS-II interface Why: 1. UHS-II card support Legacy Interface and UHS-II interface How: a) Using 3.13.2 Card Interface Detection Sequence 1. power up, host provides RCLK and STB.L to D0.lane. 2. host waits D1.lane to change EIDL to STB.L 3. host starts UHS-II initialization if STB.L > > To be clear, I don't need in-depth details, as that should be > described in each patch's commit message, but I would appreciate an > overall description of the approach you have taken to implement this. > > The reason I need this is because UHS-II is a completely new > interface/protocol. If it wasn't because that a UHS-II card is also > required to be backwards compatible with the legacy SD interface, one > could even consider introducing an entirely new subsystem. Not saying > that we should, but just pointing out that the series is not trivial > to review. > > That said, I am going to give it a real try to do the review. I will > try to focus on the overall approach, rather than on the details, at > least to start with. > Thank you, I will be patient. > > > > 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 > > I like these comparisons, thanks for sharing! > > What UHS-II interface mode does you HW support? FD156, HD312, FD312 FD624? GL9755 supports up to HD312. > > > > > 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 > > > > AKASHI Takahiro (15): > > mmc: core: UHS-II support, modify power-up sequence > > mmc: core: UHS-II support, skip set_chip_select() > > mmc: core: UHS-II support, skip TMODE setup in some cases > > mmc: core: UHS-II support, generate UHS-II SD command packet > > mmc: core: UHS-II support, set APP_CMD bit if necessary > > mmc: sdhci: add a kernel configuration for enabling UHS-II support > > mmc: sdhci: add UHS-II related definitions in headers > > mmc: sdhci: UHS-II support, dump UHS-II registers > > mmc: sdhci: UHS-II support, export host operations to core > > mmc: sdhci: UHS-II support, skip signal_voltage_switch() > > mmc: sdhci: UHS-II support, handle vdd2 in case of power-off > > mmc: sdhci: UHS-II support, modify set_power() to handle vdd2 > > mmc: sdhci: UHS-II support, export helper functions to a module > > mmc: sdhci: UHS-II support, implement operations as a module > > mmc: core: add post-mmc_attach_sd hook > > > > Ben Chuang (6): > > mmc: add UHS-II related definitions in public headers > > mmc: core: UHS-II support, try to select UHS-II interface > > mmc: sdhci: UHS-II support, add hooks for additional operations > > mmc: sdhci-uhs2: add pre-detect_init hook > > mmc: sdhci-uhs2: add post-mmc_attach_sd hook > > mmc: sdhci-pci-gli: enable UHS-II mode for GL9755 > > > > drivers/mmc/core/Makefile | 2 +- > > drivers/mmc/core/block.c | 7 +- > > drivers/mmc/core/bus.c | 5 +- > > drivers/mmc/core/core.c | 119 +++- > > drivers/mmc/core/regulator.c | 14 + > > drivers/mmc/core/sd.c | 32 ++ > > drivers/mmc/core/sd_ops.c | 12 + > > drivers/mmc/core/uhs2.c | 874 ++++++++++++++++++++++++++++++ > > Nitpick: > > I would prefer to prefix any new needed file with sd_*. In this case, > sd_uhs2.c|h. OK, change uhs2.c and uhs2.h to sd_uhs2.c and sd_uhs2.h later. > > > drivers/mmc/core/uhs2.h | 21 + > > drivers/mmc/host/Kconfig | 10 + > > drivers/mmc/host/Makefile | 1 + > > drivers/mmc/host/sdhci-omap.c | 2 +- > > drivers/mmc/host/sdhci-pci-core.c | 4 +- > > drivers/mmc/host/sdhci-pci-gli.c | 361 +++++++++++- > > drivers/mmc/host/sdhci-pxav3.c | 4 +- > > drivers/mmc/host/sdhci-uhs2.c | 797 +++++++++++++++++++++++++++ > > drivers/mmc/host/sdhci-uhs2.h | 215 ++++++++ > > drivers/mmc/host/sdhci-xenon.c | 4 +- > > drivers/mmc/host/sdhci.c | 321 +++++++++-- > > drivers/mmc/host/sdhci.h | 113 +++- > > include/linux/mmc/card.h | 1 + > > include/linux/mmc/core.h | 6 + > > include/linux/mmc/host.h | 31 ++ > > include/linux/mmc/uhs2.h | 268 +++++++++ > > 24 files changed, 3151 insertions(+), 73 deletions(-) > > create mode 100644 drivers/mmc/core/uhs2.c > > create mode 100644 drivers/mmc/core/uhs2.h > > create mode 100644 drivers/mmc/host/sdhci-uhs2.c > > create mode 100644 drivers/mmc/host/sdhci-uhs2.h > > create mode 100644 include/linux/mmc/uhs2.h > > > > -- > > 2.27.0 > > > > Kind regards > Uffe
