Commit b294ff3e authored by Asutosh Das's avatar Asutosh Das Committed by Martin K. Petersen
Browse files

scsi: ufs: core: Enable power management for wlun 



During runtime-suspend of ufs host, the SCSI devices are already suspended
and so are the queues associated with them. However, the ufs host sends SSU
(START_STOP_UNIT) to the wlun during runtime-suspend.

During the process blk_queue_enter() checks if the queue is not in suspended
state. If so, it waits for the queue to resume, and never comes out of
it. Commit 52abca64 ("scsi: block: Do not accept any requests while
suspended") adds the check to see if the queue is in suspended state in
blk_queue_enter().

Call trace:
 __switch_to+0x174/0x2c4
 __schedule+0x478/0x764
 schedule+0x9c/0xe0
 blk_queue_enter+0x158/0x228
 blk_mq_alloc_request+0x40/0xa4
 blk_get_request+0x2c/0x70
 __scsi_execute+0x60/0x1c4
 ufshcd_set_dev_pwr_mode+0x124/0x1e4
 ufshcd_suspend+0x208/0x83c
 ufshcd_runtime_suspend+0x40/0x154
 ufshcd_pltfrm_runtime_suspend+0x14/0x20
 pm_generic_runtime_suspend+0x28/0x3c
 __rpm_callback+0x80/0x2a4
 rpm_suspend+0x308/0x614
 rpm_idle+0x158/0x228
 pm_runtime_work+0x84/0xac
 process_one_work+0x1f0/0x470
 worker_thread+0x26c/0x4c8
 kthread+0x13c/0x320
 ret_from_fork+0x10/0x18

Fix this by registering ufs device wlun as a SCSI driver and registering it
for block runtime-pm. Also make this a supplier for all other LUNs. This
way the wlun device suspends after all the consumers and resumes after HBA
resumes. This also registers a new SCSI driver for rpmb wlun. This new
driver is mostly used to clear rpmb uac.

[mkp: resolve merge conflict with 5.13-rc1 and fix doc warning]

Fixed smatch warnings:
Reported-by: default avatarkernel test robot <lkp@intel.com>
Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>

Link: https://lore.kernel.org/r/4662c462e79e3e7f541f54f88f8993f421026d83.1619223249.git.asutoshd@codeaurora.org


Reviewed-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Co-developed-by: default avatarCan Guo <cang@codeaurora.org>
Signed-off-by: default avatarCan Guo <cang@codeaurora.org>
Signed-off-by: default avatarAsutosh Das <asutoshd@codeaurora.org>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent ed26297d

drivers/scsi/ufs/cdns-pltfrm.c

+2 −0
Original line number Diff line number Diff line
@@ -323,6 +323,8 @@ static const struct dev_pm_ops cdns_ufs_dev_pm_ops = { 
	.runtime_suspend = ufshcd_pltfrm_runtime_suspend,

	.runtime_resume  = ufshcd_pltfrm_runtime_resume,

	.runtime_idle    = ufshcd_pltfrm_runtime_idle,

	.prepare	 = ufshcd_suspend_prepare,

	.complete	 = ufshcd_resume_complete,

};



static struct platform_driver cdns_ufs_pltfrm_driver = {

drivers/scsi/ufs/tc-dwc-g210-pci.c

+2 −0
Original line number Diff line number Diff line
@@ -148,6 +148,8 @@ static const struct dev_pm_ops tc_dwc_g210_pci_pm_ops = { 
	.runtime_suspend = tc_dwc_g210_pci_runtime_suspend,

	.runtime_resume  = tc_dwc_g210_pci_runtime_resume,

	.runtime_idle    = tc_dwc_g210_pci_runtime_idle,

	.prepare	 = ufshcd_suspend_prepare,

	.complete	 = ufshcd_resume_complete,

};



static const struct pci_device_id tc_dwc_g210_pci_tbl[] = {

drivers/scsi/ufs/ufs-debugfs.c

+3 −3
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ void __init ufs_debugfs_init(void) 
	ufs_debugfs_root = debugfs_create_dir("ufshcd", NULL);

}



void __exit ufs_debugfs_exit(void)

void ufs_debugfs_exit(void)

{

	debugfs_remove_recursive(ufs_debugfs_root);

}
@@ -60,14 +60,14 @@ __acquires(&hba->host_sem) 
		up(&hba->host_sem);

		return -EBUSY;

	}

	pm_runtime_get_sync(hba->dev);

	ufshcd_rpm_get_sync(hba);

	return 0;

}



static void ufs_debugfs_put_user_access(struct ufs_hba *hba)

__releases(&hba->host_sem)

{

	pm_runtime_put_sync(hba->dev);

	ufshcd_rpm_put_sync(hba);

	up(&hba->host_sem);

}

drivers/scsi/ufs/ufs-debugfs.h

+1 −1
Original line number Diff line number Diff line
@@ -9,7 +9,7 @@ struct ufs_hba; 


#ifdef CONFIG_DEBUG_FS

void __init ufs_debugfs_init(void);

void __exit ufs_debugfs_exit(void);

void ufs_debugfs_exit(void);

void ufs_debugfs_hba_init(struct ufs_hba *hba);

void ufs_debugfs_hba_exit(struct ufs_hba *hba);

void ufs_debugfs_exception_event(struct ufs_hba *hba, u16 status);

drivers/scsi/ufs/ufs-exynos.c

+2 −0
Original line number Diff line number Diff line
@@ -1267,6 +1267,8 @@ static const struct dev_pm_ops exynos_ufs_pm_ops = { 
	.runtime_suspend = ufshcd_pltfrm_runtime_suspend,

	.runtime_resume  = ufshcd_pltfrm_runtime_resume,

	.runtime_idle    = ufshcd_pltfrm_runtime_idle,

	.prepare	 = ufshcd_suspend_prepare,

	.complete	 = ufshcd_resume_complete,

};



static struct platform_driver exynos_ufs_pltform = {