talos-obmc-linux/include/linux/mmc/card.h, branch v5.0

mmc: block: handle complete_work on separate workqueue

2019-02-08T11:24:17+00:00

The kblockd workqueue is created with the WQ_MEM_RECLAIM flag set. This generates a rescuer thread for that queue that will trigger when the CPU is under heavy load and collect the uncompleted work. In the case of mmc, this creates the possibility of a deadlock when there are multiple partitions on the device as other blk-mq work is also run on the same queue. For example: - worker 0 claims the mmc host to work on partition 1 - worker 1 attempts to claim the host for partition 2 but has to wait for worker 0 to finish - worker 0 schedules complete_work to release the host - rescuer thread is triggered after time-out and collects the dangling work - rescuer thread attempts to complete the work in order starting with claim host - the task to release host is now blocked by a task to claim it and will never be called The above results in multiple hung tasks that lead to failures to mount partitions. Handling complete_work on a separate workqueue avoids this by keeping the work completion tasks separate from the other blk-mq work. This allows the host to be released without getting blocked by other tasks attempting to claim the host. Signed-off-by: Zachary Hays Fixes: 81196976ed94 ("mmc: block: Add blk-mq support") Cc: Signed-off-by: Ulf Hansson

mmc: sd: Define name for default speed dtr

2018-05-29T10:24:26+00:00

Add a new define for the sd default speed 25MHz case Signed-off-by: Yinbo Zhu Signed-off-by: Ulf Hansson

mmc: core: Add a new quirk for limiting clock rate

2018-05-02T13:08:39+00:00

This patch adds a quirk to limit clock rate which can be used to reduce the SDIO clock rate for some chips with broken UHS. Signed-off-by: Harish Jenny K N Reviewed-by: Shawn Lin Signed-off-by: Ulf Hansson

mmc: core: correct taac parameter according to the specification

2017-08-30T12:01:46+00:00

Per the spec of JESD84-B51, section 7.3, replace tacc with taac to fix the obvious typo. Signed-off-by: Shawn Lin Signed-off-by: Ulf Hansson

mmc: core: Allocate per-request data using the block layer core

2017-06-20T08:30:17+00:00

The mmc_queue_req is a per-request state container the MMC core uses to carry bounce buffers, pointers to asynchronous requests and so on. Currently allocated as a static array of objects, then as a request comes in, a mmc_queue_req is assigned to it, and used during the lifetime of the request. This is backwards compared to how other block layer drivers work: they usally let the block core provide a per-request struct that get allocated right beind the struct request, and which can be obtained using the blk_mq_rq_to_pdu() helper. (The _mq_ infix in this function name is misleading: it is used by both the old and the MQ block layer.) The per-request struct gets allocated to the size stored in the queue variable .cmd_size initialized using the .init_rq_fn() and cleaned up using .exit_rq_fn(). The block layer code makes the MMC core rely on this mechanism to allocate the per-request mmc_queue_req state container. Doing this make a lot of complicated queue handling go away. We only need to keep the .qnct that keeps count of how many request are currently being processed by the MMC layer. The MQ block layer will replace also this once we transition to it. Doing this refactoring is necessary to move the ioctl() operations into custom block layer requests tagged with REQ_OP_DRV_[IN|OUT] instead of the custom code using the BigMMCHostLock that we have today: those require that per-request data be obtainable easily from a request after creating a custom request with e.g.: struct request *rq = blk_get_request(q, REQ_OP_DRV_IN, __GFP_RECLAIM); struct mmc_queue_req *mq_rq = req_to_mq_rq(rq); And this is not possible with the current construction, as the request is not immediately assigned the per-request state container, but instead it gets assigned when the request finally enters the MMC queue, which is way too late for custom requests. Signed-off-by: Linus Walleij [Ulf: Folded in the fix to drop a call to blk_cleanup_queue()] Signed-off-by: Ulf Hansson Tested-by: Heiner Kallweit

mmc: core: Export API to allow hosts to get the card address

2017-04-24T19:49:15+00:00

Some hosts controllers, like Cavium, needs to know whether the card operates in byte- or block-address mode. Therefore export a new API, mmc_card_is_blockaddr(), which provides this information. Signed-off-by: Ulf Hansson Signed-off-by: Steven J. Hill Acked-by: David Daney

mmc: mmc_test: Disable Command Queue while mmc_test is used

2017-04-24T19:42:02+00:00

Normal read and write commands may not be used while the command queue is enabled. Disable the Command Queue when mmc_test is probed and re-enable it when it is removed. Signed-off-by: Adrian Hunter Reviewed-by: Harjani Ritesh Reviewed-by: Linus Walleij Signed-off-by: Ulf Hansson

mmc: mmc: Add functions to enable / disable the Command Queue

2017-04-24T19:42:02+00:00

Add helper functions to enable or disable the Command Queue. Signed-off-by: Adrian Hunter Reviewed-by: Linus Walleij Signed-off-by: Ulf Hansson

mmc: queue: Share mmc request array between partitions

2017-04-24T19:42:01+00:00

eMMC can have multiple internal partitions that are represented as separate disks / queues. However switching between partitions is only done when the queue is empty. Consequently the array of mmc requests that are queued can be shared between partitions saving memory. Keep a pointer to the mmc request queue on the card, and use that instead of allocating a new one for each partition. Signed-off-by: Adrian Hunter Reviewed-by: Linus Walleij Signed-off-by: Ulf Hansson

mmc: Adding AUTO_BKOPS_EN bit set for Auto BKOPS support

2017-02-14T08:11:00+00:00

Adding dedicated flag for AUTO_BKOPS in card->ext_csd structure. Read AUTO_BKOPS bit value from the device EXT_CSD and set to the card->ext_csd structure. In mmc_decode_ext_csd() add a print message in case the AUTO_BKOPS is enabled Signed-off-by: Uri Yanai Signed-off-by: Alex Lemberg Signed-off-by: Ulf Hansson