From patchwork Thu Nov 24 11:24:58 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Ferre X-Patchwork-Id: 9445299 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F3524606DB for ; Thu, 24 Nov 2016 11:27:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D658E27D76 for ; Thu, 24 Nov 2016 11:27:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CB26627DCE; Thu, 24 Nov 2016 11:27:44 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 641D527D76 for ; Thu, 24 Nov 2016 11:27:44 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1c9sAT-0000jK-G2; Thu, 24 Nov 2016 11:26:17 +0000 Received: from exsmtp01.microchip.com ([198.175.253.37] helo=email.microchip.com) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1c9s9s-0008MA-Jm for linux-arm-kernel@lists.infradead.org; Thu, 24 Nov 2016 11:25:42 +0000 Received: from tenerife.corp.atmel.com (10.10.76.4) by CHN-SV-EXCH01.mchp-main.com (10.10.76.37) with Microsoft SMTP Server id 14.3.181.6; Thu, 24 Nov 2016 04:25:22 -0700 From: Nicolas Ferre To: Mark Brown , Subject: [PATCH 2/5] spi: atmel: Use core SPI_MASTER_MUST_[RT]X handling Date: Thu, 24 Nov 2016 12:24:58 +0100 Message-ID: <86f613a36c2e7db07c3ec7d0b8a650cdb9222b32.1479985886.git.nicolas.ferre@atmel.com> X-Mailer: git-send-email 2.9.0 In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20161124_032540_783966_48CB0221 X-CRM114-Status: GOOD ( 16.35 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicolas Ferre , linux-kernel@vger.kernel.org, geert@linux-m68k.org, alexandre.belloni@free-electrons.com, cyrille.pitchen@atmel.com, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP We need both RX and TX data for each transfer in any case (PIO, PDC, DMA). So convert the driver to the core dummy buffer handling with the SPI_MASTER_MUST_RX/SPI_MASTER_MUST_TX infrastructure. This move changes the maximum PDC/DMA buffer handling to 65535 bytes instead of a single page and sets master->max_dma_len to this value. All dummy buffer management is removed from the driver. Signed-off-by: Nicolas Ferre --- drivers/spi/spi-atmel.c | 131 +++++++++++++----------------------------------- 1 file changed, 35 insertions(+), 96 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index 68e22bf94647..d0a56e11e148 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -304,10 +304,6 @@ struct atmel_spi { struct completion xfer_completion; - /* scratch buffer */ - void *buffer; - dma_addr_t buffer_dma; - struct atmel_spi_caps caps; bool use_dma; @@ -328,7 +324,7 @@ struct atmel_spi_device { u32 csr; }; -#define BUFFER_SIZE PAGE_SIZE +#define SPI_MAX_DMA_XFER 65535 /* true for both PDC and DMA */ #define INVALID_DMA_ADDRESS 0xffffffff /* @@ -613,14 +609,10 @@ static void atmel_spi_next_xfer_single(struct spi_master *master, cpu_relax(); } - if (xfer->tx_buf) { - if (xfer->bits_per_word > 8) - spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos)); - else - spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos)); - } else { - spi_writel(as, TDR, 0); - } + if (xfer->bits_per_word > 8) + spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos)); + else + spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos)); dev_dbg(master->dev.parent, " start pio xfer %p: len %u tx %p rx %p bitpw %d\n", @@ -667,17 +659,12 @@ static void atmel_spi_next_xfer_fifo(struct spi_master *master, /* Fill TX FIFO */ while (num_data >= 2) { - if (xfer->tx_buf) { - if (xfer->bits_per_word > 8) { - td0 = *words++; - td1 = *words++; - } else { - td0 = *bytes++; - td1 = *bytes++; - } + if (xfer->bits_per_word > 8) { + td0 = *words++; + td1 = *words++; } else { - td0 = 0; - td1 = 0; + td0 = *bytes++; + td1 = *bytes++; } spi_writel(as, TDR, (td1 << 16) | td0); @@ -685,14 +672,10 @@ static void atmel_spi_next_xfer_fifo(struct spi_master *master, } if (num_data) { - if (xfer->tx_buf) { - if (xfer->bits_per_word > 8) - td0 = *words++; - else - td0 = *bytes++; - } else { - td0 = 0; - } + if (xfer->bits_per_word > 8) + td0 = *words++; + else + td0 = *bytes++; spi_writew(as, TDR, td0); num_data--; @@ -751,24 +734,14 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master, /* prepare the RX dma transfer */ sg_init_table(&as->dma.sgrx, 1); - if (xfer->rx_buf) { - as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen; - } else { - as->dma.sgrx.dma_address = as->buffer_dma; - if (len > BUFFER_SIZE) - len = BUFFER_SIZE; - } + as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen; /* prepare the TX dma transfer */ sg_init_table(&as->dma.sgtx, 1); - if (xfer->tx_buf) { - as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen; - } else { - as->dma.sgtx.dma_address = as->buffer_dma; - if (len > BUFFER_SIZE) - len = BUFFER_SIZE; - memset(as->buffer, 0, len); - } + as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen; + + if (len > master->max_dma_len) + len = master->max_dma_len; sg_dma_len(&as->dma.sgtx) = len; sg_dma_len(&as->dma.sgrx) = len; @@ -835,25 +808,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master, struct atmel_spi *as = spi_master_get_devdata(master); u32 len = *plen; - /* use scratch buffer only when rx or tx data is unspecified */ - if (xfer->rx_buf) - *rx_dma = xfer->rx_dma + xfer->len - *plen; - else { - *rx_dma = as->buffer_dma; - if (len > BUFFER_SIZE) - len = BUFFER_SIZE; - } - - if (xfer->tx_buf) - *tx_dma = xfer->tx_dma + xfer->len - *plen; - else { - *tx_dma = as->buffer_dma; - if (len > BUFFER_SIZE) - len = BUFFER_SIZE; - memset(as->buffer, 0, len); - dma_sync_single_for_device(&as->pdev->dev, - as->buffer_dma, len, DMA_TO_DEVICE); - } + *rx_dma = xfer->rx_dma + xfer->len - *plen; + *tx_dma = xfer->tx_dma + xfer->len - *plen; + if (len > master->max_dma_len) + len = master->max_dma_len; *plen = len; } @@ -1027,16 +985,12 @@ atmel_spi_pump_single_data(struct atmel_spi *as, struct spi_transfer *xfer) u16 *rxp16; unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; - if (xfer->rx_buf) { - if (xfer->bits_per_word > 8) { - rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos); - *rxp16 = spi_readl(as, RDR); - } else { - rxp = ((u8 *)xfer->rx_buf) + xfer_pos; - *rxp = spi_readl(as, RDR); - } + if (xfer->bits_per_word > 8) { + rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos); + *rxp16 = spi_readl(as, RDR); } else { - spi_readl(as, RDR); + rxp = ((u8 *)xfer->rx_buf) + xfer_pos; + *rxp = spi_readl(as, RDR); } if (xfer->bits_per_word > 8) { if (as->current_remaining_bytes > 2) @@ -1075,12 +1029,10 @@ atmel_spi_pump_fifo_data(struct atmel_spi *as, struct spi_transfer *xfer) /* Read data */ while (num_data) { rd = spi_readl(as, RDR); - if (xfer->rx_buf) { - if (xfer->bits_per_word > 8) - *words++ = rd; - else - *bytes++ = rd; - } + if (xfer->bits_per_word > 8) + *words++ = rd; + else + *bytes++ = rd; num_data--; } } @@ -1562,29 +1514,22 @@ static int atmel_spi_probe(struct platform_device *pdev) master->bus_num = pdev->id; master->num_chipselect = master->dev.of_node ? 0 : 4; master->setup = atmel_spi_setup; + master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX); master->transfer_one_message = atmel_spi_transfer_one_message; master->cleanup = atmel_spi_cleanup; master->auto_runtime_pm = true; + master->max_dma_len = SPI_MAX_DMA_XFER; platform_set_drvdata(pdev, master); as = spi_master_get_devdata(master); - /* - * Scratch buffer is used for throwaway rx and tx data. - * It's coherent to minimize dcache pollution. - */ - as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE, - &as->buffer_dma, GFP_KERNEL); - if (!as->buffer) - goto out_free; - spin_lock_init(&as->lock); as->pdev = pdev; as->regs = devm_ioremap_resource(&pdev->dev, regs); if (IS_ERR(as->regs)) { ret = PTR_ERR(as->regs); - goto out_free_buffer; + goto out_unmap_regs; } as->phybase = regs->start; as->irq = irq; @@ -1685,9 +1630,6 @@ static int atmel_spi_probe(struct platform_device *pdev) clk_disable_unprepare(clk); out_free_irq: out_unmap_regs: -out_free_buffer: - dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, - as->buffer_dma); out_free: spi_master_put(master); return ret; @@ -1712,9 +1654,6 @@ static int atmel_spi_remove(struct platform_device *pdev) spi_readl(as, SR); spin_unlock_irq(&as->lock); - dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, - as->buffer_dma); - clk_disable_unprepare(as->clk); pm_runtime_put_noidle(&pdev->dev);