mmc: meson-gx: remove redundant mmc_request_done() call from irq context

The call to mmc_request_done() can schedule, so it must not be called
from irq context. Wake the irq thread if it needs to be called, and let
its existing logic do its work.

Fixes the following kernel bug, which appears when running an RT patched
kernel on the AmLogic Meson AXG A113X SoC:
[   11.111407] BUG: scheduling while atomic: kworker/0:1H/75/0x00010001
[   11.111438] Modules linked in:
[   11.111451] CPU: 0 PID: 75 Comm: kworker/0:1H Not tainted 6.4.0-rc3-rt2-rtx-00081-gfd07f41ed6b4-dirty #1
[   11.111461] Hardware name: RTX AXG A113X Linux Platform Board (DT)
[   11.111469] Workqueue: kblockd blk_mq_run_work_fn
[   11.111492] Call trace:
[   11.111497]  dump_backtrace+0xac/0xe8
[   11.111510]  show_stack+0x18/0x28
[   11.111518]  dump_stack_lvl+0x48/0x60
[   11.111530]  dump_stack+0x18/0x24
[   11.111537]  __schedule_bug+0x4c/0x68
[   11.111548]  __schedule+0x80/0x574
[   11.111558]  schedule_loop+0x2c/0x50
[   11.111567]  schedule_rtlock+0x14/0x20
[   11.111576]  rtlock_slowlock_locked+0x468/0x730
[   11.111587]  rt_spin_lock+0x40/0x64
[   11.111596]  __wake_up_common_lock+0x5c/0xc4
[   11.111610]  __wake_up+0x18/0x24
[   11.111620]  mmc_blk_mq_req_done+0x68/0x138
[   11.111633]  mmc_request_done+0x104/0x118
[   11.111644]  meson_mmc_request_done+0x38/0x48
[   11.111654]  meson_mmc_irq+0x128/0x1f0
[   11.111663]  __handle_irq_event_percpu+0x70/0x114
[   11.111674]  handle_irq_event_percpu+0x18/0x4c
[   11.111683]  handle_irq_event+0x80/0xb8
[   11.111691]  handle_fasteoi_irq+0xa4/0x120
[   11.111704]  handle_irq_desc+0x20/0x38
[   11.111712]  generic_handle_domain_irq+0x1c/0x28
[   11.111721]  gic_handle_irq+0x8c/0xa8
[   11.111735]  call_on_irq_stack+0x24/0x4c
[   11.111746]  do_interrupt_handler+0x88/0x94
[   11.111757]  el1_interrupt+0x34/0x64
[   11.111769]  el1h_64_irq_handler+0x18/0x24
[   11.111779]  el1h_64_irq+0x64/0x68
[   11.111786]  __add_wait_queue+0x0/0x4c
[   11.111795]  mmc_blk_rw_wait+0x84/0x118
[   11.111804]  mmc_blk_mq_issue_rq+0x5c4/0x654
[   11.111814]  mmc_mq_queue_rq+0x194/0x214
[   11.111822]  blk_mq_dispatch_rq_list+0x3ac/0x528
[   11.111834]  __blk_mq_sched_dispatch_requests+0x340/0x4d0
[   11.111847]  blk_mq_sched_dispatch_requests+0x38/0x70
[   11.111858]  blk_mq_run_work_fn+0x3c/0x70
[   11.111865]  process_one_work+0x17c/0x1f0
[   11.111876]  worker_thread+0x1d4/0x26c
[   11.111885]  kthread+0xe4/0xf4
[   11.111894]  ret_from_fork+0x10/0x20

Fixes: 51c5d84 ("MMC: meson: initial support for GX platforms")
Cc: [email protected]
Signed-off-by: Martin Hundebøll <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Ulf Hansson <[email protected]>

Author: hundeboll

drivers/mmc/host/meson-gx-mmc.c

@@ -991,11 +991,8 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
 
 		if (data && !cmd->error)
 			data->bytes_xfered = data->blksz * data->blocks;
-		if (meson_mmc_bounce_buf_read(data) ||
-		    meson_mmc_get_next_command(cmd))
-			ret = IRQ_WAKE_THREAD;
-		else
-			ret = IRQ_HANDLED;
+
+		return IRQ_WAKE_THREAD;
 	}
 
 out:
@@ -1007,9 +1004,6 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
 		writel(start, host->regs + SD_EMMC_START);
 	}
 
-	if (ret == IRQ_HANDLED)
-		meson_mmc_request_done(host->mmc, cmd->mrq);
-
 	return ret;
 }