CVS commit: src/sys/arch/arm/broadcom

[Nick Hudson]

Module Name:    src
Committed By:   skrll
Date:           Tue Nov 25 14:30:05 UTC 2014

Modified Files:
        src/sys/arch/arm/broadcom: bcm2835_emmc.c

Log Message:
Only use 128-bit mode when the transfer is a multiple of this.

>From Jared (the arm periph guy)


To generate a diff of this commit:
cvs rdiff -u -r1.19 -r1.20 src/sys/arch/arm/broadcom/bcm2835_emmc.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/arch/arm/broadcom/bcm2835_emmc.c
diff -u src/sys/arch/arm/broadcom/bcm2835_emmc.c:1.19 src/sys/arch/arm/broadcom/bcm2835_emmc.c:1.20
--- src/sys/arch/arm/broadcom/bcm2835_emmc.c:1.19	Sat Oct  4 18:10:04 2014
+++ src/sys/arch/arm/broadcom/bcm2835_emmc.c	Tue Nov 25 14:30:05 2014
@@ -1,4 +1,4 @@
-/*	$NetBSD: bcm2835_emmc.c,v 1.19 2014/10/04 18:10:04 jmcneill Exp $	*/
+/*	$NetBSD: bcm2835_emmc.c,v 1.20 2014/11/25 14:30:05 skrll Exp $	*/
 
 /*-
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: bcm2835_emmc.c,v 1.19 2014/10/04 18:10:04 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: bcm2835_emmc.c,v 1.20 2014/11/25 14:30:05 skrll Exp $");
 
 #include "bcmdmac.h"
 
@@ -248,9 +248,21 @@ bcmemmc_xfer_data_dma(struct sdhc_softc 
 	for (seg = 0; seg < cmd->c_dmamap->dm_nsegs; seg++) {
 		sc->sc_cblk[seg].cb_ti =
 		    __SHIFTIN(11, DMAC_TI_PERMAP); /* e.MMC */
+		sc->sc_cblk[seg].cb_txfr_len =
+		    cmd->c_dmamap->dm_segs[seg].ds_len;
+		/*
+		 * All transfers are assumed to be multiples of 32-bits.
+		 */
+		KASSERTMSG((sc->sc_cblk[seg].cb_txfr_len & 0x3) == 0,
+		    "seg %zu len %d", seg, sc->sc_cblk[seg].cb_txfr_len);
 		if (ISSET(cmd->c_flags, SCF_CMD_READ)) {
 			sc->sc_cblk[seg].cb_ti |= DMAC_TI_DEST_INC;
-			sc->sc_cblk[seg].cb_ti |= DMAC_TI_DEST_WIDTH;
+			/*
+			 * Use 128-bit mode if transfer is a multiple of
+			 * 16-bytes.
+			 */
+			if ((sc->sc_cblk[seg].cb_txfr_len & 0xf) == 0)
+				sc->sc_cblk[seg].cb_ti |= DMAC_TI_DEST_WIDTH;
 			sc->sc_cblk[seg].cb_ti |= DMAC_TI_SRC_DREQ;
 			sc->sc_cblk[seg].cb_source_ad =
 			    BCM2835_PERIPHERALS_TO_BUS(sc->sc_physaddr +
@@ -259,7 +271,12 @@ bcmemmc_xfer_data_dma(struct sdhc_softc 
 			    cmd->c_dmamap->dm_segs[seg].ds_addr;
 		} else {
 			sc->sc_cblk[seg].cb_ti |= DMAC_TI_SRC_INC;
-			sc->sc_cblk[seg].cb_ti |= DMAC_TI_SRC_WIDTH;
+			/*
+			 * Use 128-bit mode if transfer is a multiple of
+			 * 16-bytes.
+			 */
+			if ((sc->sc_cblk[seg].cb_txfr_len & 0xf) == 0)
+				sc->sc_cblk[seg].cb_ti |= DMAC_TI_SRC_WIDTH;
 			sc->sc_cblk[seg].cb_ti |= DMAC_TI_DEST_DREQ;
 			sc->sc_cblk[seg].cb_source_ad =
 			    cmd->c_dmamap->dm_segs[seg].ds_addr;
@@ -267,8 +284,6 @@ bcmemmc_xfer_data_dma(struct sdhc_softc 
 			    BCM2835_PERIPHERALS_TO_BUS(sc->sc_physaddr +
 			    SDHC_DATA);
 		}
-		sc->sc_cblk[seg].cb_txfr_len =
-		    cmd->c_dmamap->dm_segs[seg].ds_len;
 		sc->sc_cblk[seg].cb_stride = 0;
 		if (seg == cmd->c_dmamap->dm_nsegs - 1) {
 			sc->sc_cblk[seg].cb_ti |= DMAC_TI_WAIT_RESP;