diff options
| author | Ioan Nicu <ioan.nicu.ext@nokia.com> | 2017-10-03 16:15:13 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-03 17:54:24 -0700 |
| commit | 31d1e130f4a0f8f629a460167569577cac9b17c1 (patch) | |
| tree | ea592c410053b35919ddbd5b116480598e6d957b /arch/powerpc/sysdev/fsl_rmu.c | |
| parent | 57148a64e823bb1f49112fa52a92a7f372cda892 (diff) | |
| download | linux-31d1e130f4a0f8f629a460167569577cac9b17c1.tar.bz2 | |
rapidio: remove global irq spinlocks from the subsystem
Locking of config and doorbell operations should be done only if the
underlying hardware requires it.
This patch removes the global spinlocks from the rapidio subsystem and
moves them to the mport drivers (fsl_rio and tsi721), only to the
necessary places. For example, local config space read and write
operations (lcread/lcwrite) are atomic in all existing drivers, so there
should be no need for locking, while the cread/cwrite operations which
generate maintenance transactions need to be synchronized with a lock.
Later, each driver could chose to use a per-port lock instead of a
global one, or even more granular locking.
Link: http://lkml.kernel.org/r/20170824113023.GD50104@nokia.com
Signed-off-by: Ioan Nicu <ioan.nicu.ext@nokia.com>
Signed-off-by: Frank Kunz <frank.kunz@nokia.com>
Acked-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/powerpc/sysdev/fsl_rmu.c')
| -rw-r--r-- | arch/powerpc/sysdev/fsl_rmu.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/fsl_rmu.c b/arch/powerpc/sysdev/fsl_rmu.c index ab7a74c75be8..88b35a3dcdc5 100644 --- a/arch/powerpc/sysdev/fsl_rmu.c +++ b/arch/powerpc/sysdev/fsl_rmu.c @@ -104,6 +104,8 @@ #define DOORBELL_MESSAGE_SIZE 0x08 +static DEFINE_SPINLOCK(fsl_rio_doorbell_lock); + struct rio_msg_regs { u32 omr; u32 osr; @@ -626,9 +628,13 @@ err_out: int fsl_rio_doorbell_send(struct rio_mport *mport, int index, u16 destid, u16 data) { + unsigned long flags; + pr_debug("fsl_doorbell_send: index %d destid %4.4x data %4.4x\n", index, destid, data); + spin_lock_irqsave(&fsl_rio_doorbell_lock, flags); + /* In the serial version silicons, such as MPC8548, MPC8641, * below operations is must be. */ @@ -638,6 +644,8 @@ int fsl_rio_doorbell_send(struct rio_mport *mport, out_be32(&dbell->dbell_regs->oddatr, (index << 20) | data); out_be32(&dbell->dbell_regs->odmr, 0x00000001); + spin_unlock_irqrestore(&fsl_rio_doorbell_lock, flags); + return 0; } |