kernel/linux.git/include/linux/mmc/host.h, branch linux-5.8.y

mmc: host: Drop redundant MMC_CAP_ERASE

2020-05-28T09:22:14+00:00

The MMC_CAP_ERASE bit is no longer used by the mmc core as erase, discard and trim operations are now always supported. Therefore, drop the bit and move all mmc hosts away from using it. Signed-off-by: Ulf Hansson Reviewed-by: Rui Miguel Silva Link: https://lore.kernel.org/r/20200508112902.23575-1-ulf.hansson@linaro.org Reviewed-by: Linus Walleij

mmc: host: Introduce the request_atomic() for the host

2020-05-28T09:20:59+00:00

The SD host controller can process one request in the atomic context if the card is nonremovable, which means we can submit next request in the irq hard handler when using the MMC host software queue to reduce the latency. Thus this patch adds a new API request_atomic() for the host controller, as well as adding support for host software queue to submit a request by the new request_atomic() API. Moreover there is an unusual case that the card is busy when trying to send a command, and we can not polling the card status in interrupt context by using request_atomic() to dispatch requests. Thus we should queue a work to try again in the non-atomic context in case the host releases the busy signal later. Suggested-by: Adrian Hunter Acked-by: Adrian Hunter Signed-off-by: Baolin Wang Link: https://lore.kernel.org/r/a344e27e506cb2329073cbd5cf65e15cc3cbeba9.1586744073.git.baolin.wang7@gmail.com Signed-off-by: Ulf Hansson

mmc: Replace zero-length array with flexible-array member

2020-03-24T13:39:45+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/20200226223125.GA20630@embeddedor Signed-off-by: Ulf Hansson

mmc: sdhci_am654: Update OTAPDLY writes

2020-03-24T13:35:41+00:00

According to the latest AM65x Data Manual[1], a different output tap delay value is optimum for a given speed mode. Therefore, deprecate the ti,otap-del-sel binding and introduce a new binding for each of the possible MMC/SD speed modes. If the legacy mode is not found, fall back to old binding to maintain dts compatibility. [1] http://www.ti.com/lit/gpn/am6526 Signed-off-by: Faiz Abbas Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/20200108150920.14547-3-faiz_abbas@ti.com Signed-off-by: Ulf Hansson

mmc: Add MMC host software queue support

2020-03-24T13:35:39+00:00

Now the MMC read/write stack will always wait for previous request is completed by mmc_blk_rw_wait(), before sending a new request to hardware, or queue a work to complete request, that will bring context switching overhead and spend some extra time to poll the card for busy completion for I/O writes via sending CMD13, especially for high I/O per second rates, to affect the IO performance. Thus this patch introduces MMC software queue interface based on the hardware command queue engine's interfaces, which is similar with the hardware command queue engine's idea, that can remove the context switching. Moreover we set the default queue depth as 64 for software queue, which allows more requests to be prepared, merged and inserted into IO scheduler to improve performance, but we only allow 2 requests in flight, that is enough to let the irq handler always trigger the next request without a context switch, as well as avoiding a long latency. Moreover the host controller should support HW busy detection for I/O operations when enabling the host software queue. That means, the host controller must not complete a data transfer request, until after the card stops signals busy. From the fio testing data in cover letter, we can see the software queue can improve some performance with 4K block size, increasing about 16% for random read, increasing about 90% for random write, though no obvious improvement for sequential read and write. Moreover we can expand the software queue interface to support MMC packed request or packed command in future. Reviewed-by: Arnd Bergmann Signed-off-by: Baolin Wang Signed-off-by: Baolin Wang Link: https://lore.kernel.org/r/4409c1586a9b3ed20d57ad2faf6c262fc3ccb6e2.1581478568.git.baolin.wang7@gmail.com Signed-off-by: Ulf Hansson

mmc: core: Allow host controllers to require R1B for CMD6

2020-03-11T15:10:36+00:00

It has turned out that some host controllers can't use R1B for CMD6 and other commands that have R1B associated with them. Therefore invent a new host cap, MMC_CAP_NEED_RSP_BUSY to let them specify this. In __mmc_switch(), let's check the flag and use it to prevent R1B responses from being converted into R1. Note that, this also means that the host are on its own, when it comes to manage the busy timeout. Suggested-by: Sowjanya Komatineni Cc: Tested-by: Anders Roxell Tested-by: Sowjanya Komatineni Tested-by: Faiz Abbas Tested-By: Peter Geis Signed-off-by: Ulf Hansson

Merge tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping

2019-09-19T20:27:23+00:00

Pull dma-mapping updates from Christoph Hellwig: - add dma-mapping and block layer helpers to take care of IOMMU merging for mmc plus subsequent fixups (Yoshihiro Shimoda) - rework handling of the pgprot bits for remapping (me) - take care of the dma direct infrastructure for swiotlb-xen (me) - improve the dma noncoherent remapping infrastructure (me) - better defaults for ->mmap, ->get_sgtable and ->get_required_mask (me) - cleanup mmaping of coherent DMA allocations (me) - various misc cleanups (Andy Shevchenko, me) * tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping: (41 commits) mmc: renesas_sdhi_internal_dmac: Add MMC_CAP2_MERGE_CAPABLE mmc: queue: Fix bigger segments usage arm64: use asm-generic/dma-mapping.h swiotlb-xen: merge xen_unmap_single into xen_swiotlb_unmap_page swiotlb-xen: simplify cache maintainance swiotlb-xen: use the same foreign page check everywhere swiotlb-xen: remove xen_swiotlb_dma_mmap and xen_swiotlb_dma_get_sgtable xen: remove the exports for xen_{create,destroy}_contiguous_region xen/arm: remove xen_dma_ops xen/arm: simplify dma_cache_maint xen/arm: use dev_is_dma_coherent xen/arm: consolidate page-coherent.h xen/arm: use dma-noncoherent.h calls for xen-swiotlb cache maintainance arm: remove wrappers for the generic dma remap helpers dma-mapping: introduce a dma_common_find_pages helper dma-mapping: always use VM_DMA_COHERENT for generic DMA remap vmalloc: lift the arm flag for coherent mappings to common code dma-mapping: provide a better default ->get_required_mask dma-mapping: remove the dma_declare_coherent_memory export remoteproc: don't allow modular build ...

mmc: queue: Fix bigger segments usage

2019-09-12T12:14:09+00:00

The commit 38c38cb73223 ("mmc: queue: use bigger segments if DMA MAP layer can merge the segments") always enables the bugger segments if DMA MAP layer can merge the segments, but some controllers (SDHCI) have strictly limitation about the segments size, and then the commit breaks on the controllers. To fix the issue, this patch adds a new flag MMC_CAP2_MERGE_CAPABLE into the struct mmc_host and the bigger segments usage is disabled as default. Reported-by: Thierry Reding Fixes: 38c38cb73223 ("mmc: queue: use bigger segments if DMA MAP layer can merge the segments") Signed-off-by: Yoshihiro Shimoda Acked-by: Ulf Hansson Signed-off-by: Christoph Hellwig

mmc: core: Clarify that the ->ack_sdio_irq() callback is mandatory

2019-09-11T14:10:18+00:00

For the MMC_CAP2_SDIO_IRQ_NOTHREAD case and when using sdio_signal_irq(), the ->ack_sdio_irq() is already mandatory, which was not the case for those host drivers that called sdio_run_irqs() directly. As there are no longer any drivers calling sdio_run_irqs(), let's clarify the code by dropping the unnecessary check and explicitly state that the callback is mandatory in the header file. Tested-by: Matthias Kaehlcke Reviewed-by: Matthias Kaehlcke Signed-off-by: Ulf Hansson Reviewed-by: Douglas Anderson Signed-off-by: Ulf Hansson

mmc: core: Add helper function to indicate if SDIO IRQs is enabled

2019-09-11T14:10:18+00:00

To avoid each host driver supporting SDIO IRQs, from keeping track internally about if SDIO IRQs has been claimed, let's introduce a common helper function, sdio_irq_claimed(). The function returns true if SDIO IRQs are claimed, via using the information about the number of claimed irqs. This is safe, even without any locks, as long as the helper function is called only from runtime/system suspend callbacks of the host driver. Tested-by: Matthias Kaehlcke Signed-off-by: Ulf Hansson Reviewed-by: Douglas Anderson Signed-off-by: Ulf Hansson