powerpc/fsl_lbc: Add workaround for ELBC-A001 erratum
Simultaneous FCM and GPCM or UPM operation may erroneously trigger
bus monitor timeout.
Set the local bus monitor timeout value to the maximum by setting
LBCR[BMT] = 0 and LBCR[BMTPS] = 0xF.
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/fsl_lbc.h b/arch/powerpc/include/asm/fsl_lbc.h
index 5c1bf34..8a0b5ec 100644
--- a/arch/powerpc/include/asm/fsl_lbc.h
+++ b/arch/powerpc/include/asm/fsl_lbc.h
@@ -157,6 +157,8 @@
#define LBCR_EPAR_SHIFT 16
#define LBCR_BMT 0x0000FF00
#define LBCR_BMT_SHIFT 8
+#define LBCR_BMTPS 0x0000000F
+#define LBCR_BMTPS_SHIFT 0
#define LBCR_INIT 0x00040000
__be32 lcrr; /**< Clock Ratio Register */
#define LCRR_DBYP 0x80000000
diff --git a/arch/powerpc/sysdev/fsl_lbc.c b/arch/powerpc/sysdev/fsl_lbc.c
index 4fcb5a4..0608b16 100644
--- a/arch/powerpc/sysdev/fsl_lbc.c
+++ b/arch/powerpc/sysdev/fsl_lbc.c
@@ -184,7 +184,8 @@
}
EXPORT_SYMBOL(fsl_upm_run_pattern);
-static int __devinit fsl_lbc_ctrl_init(struct fsl_lbc_ctrl *ctrl)
+static int __devinit fsl_lbc_ctrl_init(struct fsl_lbc_ctrl *ctrl,
+ struct device_node *node)
{
struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
@@ -198,6 +199,10 @@
/* Enable interrupts for any detected events */
out_be32(&lbc->lteir, LTEIR_ENABLE);
+ /* Set the monitor timeout value to the maximum for erratum A001 */
+ if (of_device_is_compatible(node, "fsl,elbc"))
+ clrsetbits_be32(&lbc->lbcr, LBCR_BMT, LBCR_BMTPS);
+
return 0;
}
@@ -304,7 +309,7 @@
fsl_lbc_ctrl_dev->dev = &dev->dev;
- ret = fsl_lbc_ctrl_init(fsl_lbc_ctrl_dev);
+ ret = fsl_lbc_ctrl_init(fsl_lbc_ctrl_dev, dev->dev.of_node);
if (ret < 0)
goto err;