Commit 9a872def authored Jul 17, 2020 by Laurentiu Tudor Committed by Greg Kroah-Hartman Jul 23, 2020

bus: fsl-mc: use raw spin lock to serialize mc cmds



Replace the spinlock that serializes the MC commands with a raw
spinlock. This is needed for the RT kernel because there are MC
commands sent in interrupt context.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Link: https://lore.kernel.org/r/20200717154800.17169-3-ioana.ciornei@nxp.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent a3b7a581

drivers/bus/fsl-mc/mc-io.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -82,7 +82,7 @@ int __must_check fsl_create_mc_io(struct device *dev,
		mc_io->portal_phys_addr = mc_portal_phys_addr;
		mc_io->portal_size = mc_portal_size;
		if (flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
		spin_lock_init(&mc_io->spinlock);
		raw_spin_lock_init(&mc_io->spinlock);
		else
		mutex_init(&mc_io->mutex);

drivers/bus/fsl-mc/mc-sys.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -251,7 +251,7 @@ int mc_send_command(struct fsl_mc_io mc_io, struct fsl_mc_command cmd)
		return -EINVAL;

		if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
		spin_lock_irqsave(&mc_io->spinlock, irq_flags);
		raw_spin_lock_irqsave(&mc_io->spinlock, irq_flags);
		else
		mutex_lock(&mc_io->mutex);

		@@ -287,7 +287,7 @@ int mc_send_command(struct fsl_mc_io mc_io, struct fsl_mc_command cmd)
		error = 0;
		common_exit:
		if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
		spin_unlock_irqrestore(&mc_io->spinlock, irq_flags);
		raw_spin_unlock_irqrestore(&mc_io->spinlock, irq_flags);
		else
		mutex_unlock(&mc_io->mutex);

include/linux/fsl/mc.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -339,7 +339,7 @@ struct fsl_mc_io {
		* This field is only meaningful if the
		* FSL_MC_IO_ATOMIC_CONTEXT_PORTAL flag is set
		*/
		spinlock_t spinlock; /* serializes mc_send_command() */
		raw_spinlock_t spinlock; /* serializes mc_send_command() */
		};
		};