On Tue, Jan 11, 2022 at 07:07:47AM +0900, Stafford Horne wrote: > On Sun, Jan 09, 2022 at 06:20:03PM -0500, Gabriel Somlo wrote: > > LiteX (https://github.com/enjoy-digital/litex) is a SoC framework > > that targets FPGAs. LiteSDCard is a small footprint, configurable > > SDCard core commonly used in LiteX designs. > > > > The driver was first written in May 2020 and has been maintained > > cooperatively by the LiteX community. Thanks to all contributors! > > > > Co-developed-by: Kamil Rakoczy <krakoczy@xxxxxxxxxxxx> > > Signed-off-by: Kamil Rakoczy <krakoczy@xxxxxxxxxxxx> > > Co-developed-by: Maciej Dudek <mdudek@xxxxxxxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Maciej Dudek <mdudek@xxxxxxxxxxxxxxxxxxxxxxxx> > > Co-developed-by: Paul Mackerras <paulus@xxxxxxxxxx> > > Signed-off-by: Paul Mackerras <paulus@xxxxxxxxxx> > > Signed-off-by: Gabriel Somlo <gsomlo@xxxxxxxxx> > > Reviewed-by: Joel Stanley <joel@xxxxxxxxx> > > Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> > > --- > > > > New in v11: > > - picked up r/b from Andy > > drivers/mmc/host/litex_mmc.c: > > - defensive coding of litex_mmc_interrupt() return logic > > - remove `dev` member of `struct litex_mmc_host`, only used during probe > > > > >New in v10: > > >drivers/mmc/host/litex_mmc.c: > > > - group `linux/mmc/*` includes by themselves > > > - clean-up of `return` style (multiple locations throughout source) > > > - create `mmc_free_host()` wrapper for use with > > > `devm_add_action_or_reset()` > > > - use GFP_KERNEL with `dmam_alloc_coherent()` > > > > > >>New in v9: > > >>drivers/mmc/host/Kconfig: > > >> - fix OF dependency > > >>drivers/mmc/host/litex_mmc.c: > > >> - remove `linux/of.h` include, no longer needed since dropping > > >> `of_match_ptr()` > > >> - add `linux/mod_devicetable.h` include > > >> - use devm_action_or_reset() to devm-ify mmc_alloc_host(), and obviate > > >> the need to call mmc_free_host() explicitly during either probe() > > >> error path or during remove() > > >> > > >>>New in v8: > > >>> - remove `Cc:` lines from commit blurb > > >>>drivers/mmc/host/litex_mmc.c: > > >>> - fix file header comment (for real, this time) > > >>> - add explicit `bits.h` include > > >>> - remove `of_match_ptr()` wrapper from around .of_match_table argument > > >>> - fix devm ordering issues: use `devm_request_irq()`, which precludes > > >>> the need to call `free_irq()` on `probe()` error path or from `remove()` > > >>> > > >>>>New in v7: > > >>>>drivers/mmc/host/Kconfig: > > >>>> - added module name in LiteSDCard Kconfig entry > > >>>>drivers/mmc/host/litex_mmc.c: > > >>>> - fixed comment formatting, ordering, and capitalization throughout > > >>>> the entire file > > >>>> - sorted header #include statements > > >>>> - removed redundant parantheses in readx_poll_timeout() condition > > >>>> - explicit handling of readx_poll_timeout() timeout scenarios > > >>>> - dev_err() used in litex_mmc_sdcard_wait_done() > > >>>> - use memcpy_fromio() to grab command response > > >>>> - no need to apply 0xffff mask to a 32-bit value right-shifted by 16 > > >>>> (host->resp[3]) > > >>>> - use clamp() instead of min(max(...)...) > > >>>> - reworked platform_get_irq_optional() error handling logic > > >>>> - no need to explicitly zero host->irq, kzalloc() does that already > > >>>> - added missing free_irq() in litex_mmc_probe() error path > > >>>> - reordered calls inside litex_mmc_remove() (calling mmc_free_host() > > >>>> before free_irq() > > >>>> > > >>>>>New in v6: > > >>>>> - fix handling of deferred probe vs. platform_get_irq_optional() > > >>>>> - don't #ifdef dma_set_mask_and_coherent(), since it automatically > > >>>>> does the right thing on both 32- and 64-bit DMA capable arches > > >>>>> - remove MMC_CAP2_FULL_PWR_CYCLE, add MMC_CAP2_NO_MMC to list of > > >>>>> hardcoded capabilities during litex_mmc_probe() > > >>>>> - hardcode mmc->ocr_avail to the full 2.7-3.6V range allowed by the > > >>>>> SDCard spec (the LiteSDCard device doesn't accept software > > >>>>> configuration) > > >>>>> > > >>>>>>New in v5: > > >>>>>> - shorter #define constant names (cosmetic, make them less unwieldy) > > >>>>>> - picked up reviewed-by Joel > > >>>>>> > > >>>>>>>New in v4: > > >>>>>>> - struct litex_mmc_host fields re-ordered so that `pahole` reports > > >>>>>>> no holes on either 32- or 64-bit builds > > >>>>>>> - litex_mmc_set_bus_width() now encapsulates check for > > >>>>>>> host->is_bus_width_set > > >>>>>>> - litex_mmc_request() - factor out dma data setup into separate > > >>>>>>> helper function: litex_mmc_do_dma() > > >>>>>>> > > >>>>>>>> New in v3: > > >>>>>>>> - fixed function signature (no line split), and naming (litex_mmc_*) > > >>>>>>>> - more informative MODULE_AUTHOR() entries > > >>>>>>>> - also added matching "Copyright" entries in file header > > >>>>>>>> - fixed description and dependencies in Kconfig > > >>>>>>>> - removed magic constants > > >>>>>>>> - removed litex_map_status(), have sdcard_wait_done() return *real* > > >>>>>>>> error codes directly instead. > > >>>>>>>> - streamlined litex_mmc_reponse_len() > > >>>>>>>> - call litex_mmc_set_bus_width() only once, and ensure it returns > > >>>>>>>> correct error code(s) > > >>>>>>>> - use readx_poll_timeout() -- more concise -- instead of > > >>>>>>>> read_poll_timeout() > > >>>>>>>> - use dev_err() in litex_mmc_send_cmd() (instead of pr_err()) > > >>>>>>>> - litex_mmc_setclk() will update host->clock before returning > > >>>>>>>> - separate irq initialization into its own function, > > >>>>>>>> litex_mmc_irq_init() > > >>>>>>>> - document rationale for f_min, f_max > > >>>>>>>> - use dmam_alloc_coherent(), which simplifies cleanup significantly > > >>>>>>>> - bump dma_set_mask_and_coherent() to 64-bits on suitable > > >>>>>>>> architectures > > >>>>>>>> - clock source picked up from dedicated DT clock reference property > > >>>>>>>> - remove gpio card-detect logic (needs testing and a dt binding > > >>>>>>>> example before being eligible for upstream inclusion) > > >>>>>>>> - large `if (data) { ... }` block in litex_mmc_request() left as-is, > > >>>>>>>> there are too many variables shared with the rest of the parent > > >>>>>>>> function body to easily separate (e.g., `len`, `transfer`, `direct`). > > >>>>>>>> If this is indeed a blocker, I can take another shot at refactoring > > >>>>>>>> it in a future revision! > > > > drivers/mmc/host/Kconfig | 9 + > > drivers/mmc/host/Makefile | 1 + > > drivers/mmc/host/litex_mmc.c | 657 +++++++++++++++++++++++++++++++++++ > > 3 files changed, 667 insertions(+) > > create mode 100644 drivers/mmc/host/litex_mmc.c > > > > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig > > index 5af8494c31b5..8f661f52b502 100644 > > --- a/drivers/mmc/host/Kconfig > > +++ b/drivers/mmc/host/Kconfig > > @@ -1093,3 +1093,12 @@ config MMC_OWL > > > > config MMC_SDHCI_EXTERNAL_DMA > > bool > > + > > +config MMC_LITEX > > + tristate "LiteX MMC Host Controller support" > > + depends on ((PPC_MICROWATT || LITEX) && OF) || COMPILE_TEST > > + help > > + This selects support for the MMC Host Controller found in LiteX SoCs. > > See comment below. > > > + To compile this driver as a module, choose M here: the > > + module will be called litex_mmc. > > Can we add this here too? > > If unsure, say N. OK, lined up for v12. > > diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile > > index ea36d379bd3c..4e4ceb32c4b4 100644 > > --- a/drivers/mmc/host/Makefile > > +++ b/drivers/mmc/host/Makefile > > @@ -101,6 +101,7 @@ obj-$(CONFIG_MMC_CQHCI) += cqhci.o > > cqhci-y += cqhci-core.o > > cqhci-$(CONFIG_MMC_CRYPTO) += cqhci-crypto.o > > obj-$(CONFIG_MMC_HSQ) += mmc_hsq.o > > +obj-$(CONFIG_MMC_LITEX) += litex_mmc.o > > > > ifeq ($(CONFIG_CB710_DEBUG),y) > > CFLAGS-cb710-mmc += -DDEBUG > > diff --git a/drivers/mmc/host/litex_mmc.c b/drivers/mmc/host/litex_mmc.c > > new file mode 100644 > > index 000000000000..cc2848030e6b > > --- /dev/null > > +++ b/drivers/mmc/host/litex_mmc.c > > @@ -0,0 +1,657 @@ > ... > > + > > + /* Initialize clock source */ > > + clk = devm_clk_get(dev, NULL); > > + if (IS_ERR(clk)) > > + return dev_err_probe(dev, PTR_ERR(clk), "can't get clock\n"); > > + host->ref_clk = clk_get_rate(clk); > > Note, we used to have: > > cpu = of_get_next_cpu_node(NULL); > ret = of_property_read_u32(cpu, "clock-frequency", &host->freq); > of_node_put(cpu); > if (ret) { > dev_err(&pdev->dev, "No \"clock-frequency\" property in DT\n"); > goto err_free_host; > } > > As we agree, this worked but was hacky. The new use of devm_clk_get above uses > the COMMON_CLK framework. Which is great but OpenRISC doesn't yet support > COMMON_CLK, so this driver no longer works on OpenRISC. > > I think the ideal thing is to not change the driver code and I will just add > support for COMMON_CLK on openrisc (already done and tested). But as we > discussed off e-mail I think we should change the config constraints to. > > depends on ((PPC_MICROWATT || LITEX) && OF && HAVE_CLK) || COMPILE_TEST OK, also lined up for v12. I'll probably send out v12 in a few hours -- thanks for the suggestions and testing! Best, --Gabriel
