Date: Wed, 3 Feb 2021 20:32:36 GMT From: Michal Meloun <mmel@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 8727c174b0fe - main - dwmmc: Multiple busdma fixes. Message-ID: <202102032032.113KWa0D070618@gitrepo.freebsd.org>
next in thread | raw e-mail | index | archive | help
The branch main has been updated by mmel: URL: https://cgit.FreeBSD.org/src/commit/?id=8727c174b0fe44766bb7ea765dac6d5f82818103 commit 8727c174b0fe44766bb7ea765dac6d5f82818103 Author: Michal Meloun <mmel@FreeBSD.org> AuthorDate: 2021-01-21 14:06:19 +0000 Commit: Michal Meloun <mmel@FreeBSD.org> CommitDate: 2021-02-03 20:15:11 +0000 dwmmc: Multiple busdma fixes. - limit maximum segment size to 2048 bytes. Although dwmmc supports a buffer fragment with a maximum length of 4095 bytes, use the nearest lower power of two as the maximum fragment size. Otherwise, busdma create excessive buffer fragments. - fix off by one error in computation of the maximum data transfer length. - in addition, reserve two DMA descriptors that can be used by busdma bouncing. The beginning or end of the buffer can be misaligned. - Don’t ignore errors passed to bus_dmamap_load() callback function. - In theory, a DMA engine may be running at time when next dma descriptor is constructed. Create a full DMA descriptor before OWN bit is set. MFC after: 2 weeks --- sys/dev/mmc/host/dwmmc.c | 47 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 32 insertions(+), 15 deletions(-) diff --git a/sys/dev/mmc/host/dwmmc.c b/sys/dev/mmc/host/dwmmc.c index 11521257ee0a..b31bb0d4e68b 100644 --- a/sys/dev/mmc/host/dwmmc.c +++ b/sys/dev/mmc/host/dwmmc.c @@ -107,8 +107,7 @@ __FBSDID("$FreeBSD$"); #define CARD_INIT_DONE 0x04 #define DWMMC_DATA_ERR_FLAGS (SDMMC_INTMASK_DRT | SDMMC_INTMASK_DCRC \ - |SDMMC_INTMASK_HTO | SDMMC_INTMASK_SBE \ - |SDMMC_INTMASK_EBE) + |SDMMC_INTMASK_SBE | SDMMC_INTMASK_EBE) #define DWMMC_CMD_ERR_FLAGS (SDMMC_INTMASK_RTO | SDMMC_INTMASK_RCRC \ |SDMMC_INTMASK_RE) #define DWMMC_ERR_FLAGS (DWMMC_DATA_ERR_FLAGS | DWMMC_CMD_ERR_FLAGS \ @@ -134,7 +133,16 @@ struct idmac_desc { #define IDMAC_DESC_SEGS (PAGE_SIZE / (sizeof(struct idmac_desc))) #define IDMAC_DESC_SIZE (sizeof(struct idmac_desc) * IDMAC_DESC_SEGS) #define DEF_MSIZE 0x2 /* Burst size of multiple transaction */ -#define IDMAC_MAX_SIZE 4096 +/* + * Size field in DMA descriptor is 13 bits long (up to 4095 bytes), + * but must be a multiple of the data bus size.Additionally, we must ensure + * that bus_dmamap_load() doesn't additionally fragments buffer (because it + * is processed with page size granularity). Thus limit fragment size to half + * of page. + * XXX switch descriptor format to array and use second buffer pointer for + * second half of page + */ +#define IDMAC_MAX_SIZE 2048 static void dwmmc_next_operation(struct dwmmc_softc *); static int dwmmc_setup_bus(struct dwmmc_softc *, int); @@ -165,8 +173,11 @@ static void dwmmc_get1paddr(void *arg, bus_dma_segment_t *segs, int nsegs, int error) { + if (nsegs != 1) + panic("%s: nsegs != 1 (%d)\n", __func__, nsegs); if (error != 0) - return; + panic("%s: error != 0 (%d)\n", __func__, error); + *(bus_addr_t *)arg = segs[0].ds_addr; } @@ -176,15 +187,13 @@ dwmmc_ring_setup(void *arg, bus_dma_segment_t *segs, int nsegs, int error) struct dwmmc_softc *sc; int idx; - if (error != 0) - return; - sc = arg; - dprintf("nsegs %d seg0len %lu\n", nsegs, segs[0].ds_len); + if (error != 0) + panic("%s: error != 0 (%d)\n", __func__, error); for (idx = 0; idx < nsegs; idx++) { - sc->desc_ring[idx].des0 = (DES0_OWN | DES0_DIC | DES0_CH); + sc->desc_ring[idx].des0 = DES0_DIC | DES0_CH; sc->desc_ring[idx].des1 = segs[idx].ds_len & DES1_BS1_MASK; sc->desc_ring[idx].des2 = segs[idx].ds_addr; @@ -195,6 +204,8 @@ dwmmc_ring_setup(void *arg, bus_dma_segment_t *segs, int nsegs, int error) sc->desc_ring[idx].des0 &= ~(DES0_DIC | DES0_CH); sc->desc_ring[idx].des0 |= DES0_LD; } + wmb(); + sc->desc_ring[idx].des0 |= DES0_OWN; } } @@ -277,7 +288,7 @@ dma_setup(struct dwmmc_softc *sc) error = bus_dma_tag_create( bus_get_dma_tag(sc->dev), /* Parent tag. */ - CACHE_LINE_SIZE, 0, /* alignment, boundary */ + 8, 0, /* alignment, boundary */ BUS_SPACE_MAXADDR_32BIT, /* lowaddr */ BUS_SPACE_MAXADDR, /* highaddr */ NULL, NULL, /* filter, filterarg */ @@ -786,7 +797,7 @@ dwmmc_attach(device_t dev) fail: mtx_unlock(&sc->sim_mtx); #endif - /* + /* * Schedule a card detection as we won't get an interrupt * if the card is inserted when we attach */ @@ -900,8 +911,8 @@ dwmmc_update_ios(device_t brdev, device_t reqdev) sc = device_get_softc(brdev); ios = &sc->host.ios; - dprintf("Setting up clk %u bus_width %d\n", - ios->clock, ios->bus_width); + dprintf("Setting up clk %u bus_width %d, timming: %d\n", + ios->clock, ios->bus_width, ios->timing); if (ios->bus_width == bus_width_8) WRITE4(sc, SDMMC_CTYPE, SDMMC_CTYPE_8BIT); @@ -985,7 +996,7 @@ dma_prepare(struct dwmmc_softc *sc, struct mmc_command *cmd) reg = READ4(sc, SDMMC_INTMASK); reg &= ~(SDMMC_INTMASK_TXDR | SDMMC_INTMASK_RXDR); WRITE4(sc, SDMMC_INTMASK, reg); - + dprintf("%s: bus_dmamap_load size: %zu\n", __func__, data->len); err = bus_dmamap_load(sc->buf_tag, sc->buf_map, data->data, data->len, dwmmc_ring_setup, sc, BUS_DMA_NOWAIT); @@ -1358,7 +1369,13 @@ dwmmc_read_ivar(device_t bus, device_t child, int which, uintptr_t *result) *(int *)result = sc->host.caps; break; case MMCBR_IVAR_MAX_DATA: - *(int *)result = (IDMAC_MAX_SIZE * IDMAC_DESC_SEGS) / MMC_SECTOR_SIZE; + /* + * Busdma may bounce buffers, so we must reserve 2 descriptors + * (on start and on end) for bounced fragments. + * + */ + *(int *)result = (IDMAC_MAX_SIZE * IDMAC_DESC_SEGS) / + MMC_SECTOR_SIZE - 3; break; case MMCBR_IVAR_TIMING: *(int *)result = sc->host.ios.timing;
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202102032032.113KWa0D070618>