Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 55d7cd74 authored by Jeremy Kerr's avatar Jeremy Kerr
Browse files

[POWERPC] spufs: fix post-stopped update of MFC_CNTL register 



We currently have two issues with the MFC save code:

 * save_mfc_decr doesn't handle a transition of 1 -> 0 of the Ds bit
 * The Q bit may be stale in the CSA

This change fixes the first issue by clearing the relevant bits from
the MFC_CNTL value in the CSA before or-ing in the updated status.
Also, we add the Q bit to the updated status.

Signed-off-by: default avatarJeremy Kerr <jk@ozlabs.org>
parent 1ca4264e

arch/powerpc/platforms/cell/spufs/switch.c

+9 −4
Original line number Diff line number Diff line
@@ -250,16 +250,21 @@ static inline void save_spu_status(struct spu_state *csa, struct spu *spu) 
	}

}



static inline void save_mfc_decr(struct spu_state *csa, struct spu *spu)

static inline void save_mfc_stopped_status(struct spu_state *csa,

		struct spu *spu)

{

	struct spu_priv2 __iomem *priv2 = spu->priv2;

	const u64 mask = MFC_CNTL_DECREMENTER_RUNNING |

			MFC_CNTL_DMA_QUEUES_EMPTY;



	/* Save, Step 12:

	 *     Read MFC_CNTL[Ds].  Update saved copy of

	 *     CSA.MFC_CNTL[Ds].

	 *

	 * update: do the same with MFC_CNTL[Q].

	 */

	csa->priv2.mfc_control_RW |=

		in_be64(&priv2->mfc_control_RW) & MFC_CNTL_DECREMENTER_RUNNING;

	csa->priv2.mfc_control_RW &= ~mask;

	csa->priv2.mfc_control_RW |= in_be64(&priv2->mfc_control_RW) & mask;

}



static inline void halt_mfc_decr(struct spu_state *csa, struct spu *spu)
@@ -1791,7 +1796,7 @@ static int quiece_spu(struct spu_state *prev, struct spu *spu) 
	save_spu_runcntl(prev, spu);	        /* Step 9. */

	save_mfc_sr1(prev, spu);	        /* Step 10. */

	save_spu_status(prev, spu);	        /* Step 11. */

	save_mfc_decr(prev, spu);	        /* Step 12. */

	save_mfc_stopped_status(prev, spu);     /* Step 12. */

	halt_mfc_decr(prev, spu);	        /* Step 13. */

	save_timebase(prev, spu);		/* Step 14. */

	remove_other_spu_access(prev, spu);	/* Step 15. */