From patchwork Sun Dec 6 01:18:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 338972 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52D96C4361B for ; Sun, 6 Dec 2020 01:20:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B7DF23128 for ; Sun, 6 Dec 2020 01:20:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726498AbgLFBUI (ORCPT ); Sat, 5 Dec 2020 20:20:08 -0500 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:35643 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726488AbgLFBUI (ORCPT ); Sat, 5 Dec 2020 20:20:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1607218758; x=1638754758; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0I4QzQzOsChmNRmAhZHgMo7j8PJFacdYYrWcPxv0oYw=; b=jKlEXqx4NHOBFY78DmCZV2/zgxZBykzLA6dx4L7iY4e4KXu+Dv4gXJDS Js7xw6o9PHhCnB4dJaizvP/nidZFsOqBogQxvQfrRvqrn2B7nkto4BhW3 U3wZMhDtgrU+uMrg9M1m2ziHxnV1JqC/ULjAh0ZcB8mUB5JIcehJMx/ML JeT5aMlvohWET2AawUoYnh6mfWDvNhrJb32frW/kATG6P2sQZ00YonQN1 OQRDCkGObGz2/UsjTacI/MNFEGxg4UXK0avDSsxtCNd8/Oa17GvxXfv5W MD8kgQNH6sv8D36szPcwiEm0f95zKrVSHddg5J+M7aGfmhbv3icL24J0F Q==; IronPort-SDR: mQ5zs72xzp4425URVPxu22ND647gae3RXyz44nEpWpVLB58FZKIBaPAcHY1lUwkcJbFp/sG7nV e4eAY2WrLohW4Cb0rePTssKsvV5rGRFDAM8VCxOI3T7psecxB+JefzgfHRawl/Rla7NT4tsEEt 0ljpsqw0lCmR1i4PGw+1d0hI8LGcDfwIcTFkKmplm56/kjb/vzrDF4ILEX5ajZHphJbUVBZmpa UWSAzS3WDC5AtpnqZ7KiD8fY+Lz877JMkpZdZDP/PaVFhbdyrdU/aQz5bEeSetJZFV1qtGvaHC uuA= X-IronPort-AV: E=Sophos;i="5.78,396,1599494400"; d="scan'208";a="258231902" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 06 Dec 2020 09:36:39 +0800 IronPort-SDR: 6oZHDvrAWUvTTjRdCSE4gNlnZWzVHDBfqi78acexTMKmdYHuXEiNZbywZz3Y/EblpvJ5Oh2/33 2/Nr/xKlXuIRTW7HjgwomNjuaFiPk2Bc0= Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2020 17:02:26 -0800 IronPort-SDR: fuEYEf2IlrLD5G/bOGkuGCDZkpkN4CKsRXw+g+I+0EwzZ2N1ZRJqQpP7XZooPxjlYDu3eDscW7 hakcDMFmSKrQ== WDCIronportException: Internal Received: from cnf005296.ad.shared (HELO twashi.fujisawa.hgst.com) ([10.84.71.167]) by uls-op-cesaip02.wdc.com with ESMTP; 05 Dec 2020 17:18:21 -0800 From: Damien Le Moal To: Serge Semin , Mark Brown , linux-spi@vger.kernel.org, Rob Herring , devicetree@vger.kernel.org Cc: Sean Anderson Subject: [PATCH v3 1/3] dt-bindings: spi: dw-apb-ssi: Add Canaan K210 SPI controller Date: Sun, 6 Dec 2020 10:18:15 +0900 Message-Id: <20201206011817.11700-2-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201206011817.11700-1-damien.lemoal@wdc.com> References: <20201206011817.11700-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Update the snps,dw-apb-ssi.yaml document to include the compatibility string "canaan,k210-spi" compatible string for the Canaan Kendryte K210 RISC-V SoC DW apb_ssi V4 SPI controller. Signed-off-by: Damien Le Moal Acked-by: Serge Semin --- Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++ 1 file changed, 2 insertions(+) diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml index 99ed9b416e94..4825157cd92e 100644 --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml @@ -65,6 +65,8 @@ properties: const: baikal,bt1-ssi - description: Baikal-T1 System Boot SPI Controller const: baikal,bt1-sys-ssi + - description: Canaan Kendryte K210 SoS SPI Controller + const: canaan,k210-spi reg: minItems: 1 From patchwork Sun Dec 6 01:18:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 339470 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 997B1C4361B for ; Sun, 6 Dec 2020 01:20:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 690EE23128 for ; Sun, 6 Dec 2020 01:20:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726023AbgLFBUe (ORCPT ); Sat, 5 Dec 2020 20:20:34 -0500 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:4736 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726488AbgLFBUd (ORCPT ); Sat, 5 Dec 2020 20:20:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1607218796; x=1638754796; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vG/A0zFrdpj+CCVOe98LHj7PBknAVZVpqI/ZrZRgmYc=; b=U0jWaFy1i58tQhWHc3KsJTRwMWr3TVznzJ54/D6E+c7AxQGkDNVt/TEM o3+c0Q7xApQwYwWtf2TLl1H0WgVhs6XCw7oLcGbOh7xOvva3cEtVTfA1v Fbo/8wlftROas9yIuBGwy0/mvmrNFH4CjG/MtRQxZu7Pwe7J9t1e28QXO jqCFHEyLpB3eFDKw3mxBuJ0AFdHtqOzwHhzYIrH7EA95YyrDiZm/QAuIb mAM8Hx+vbOQ+NKAwOQs2t0QRwhcc+G7/49PAkq8gJ/QjC3oGHQP2OGvby m9PxvOqPMBvY+lZ7OD37JDTVfa96nYpxl0e+ZamBq+AzfBTadaYmGt75+ A==; IronPort-SDR: dCEidGWVxrsijsz03dkP+KO+42N7zgjkZEOx5L5dpW5l/rZcQYs3g5vv/mm4GTQbTBJbpTjh67 +f4w/VVW6brmWZ1hUgdtXrbla5Sh2A1CiegK4IOqEJLLmPMEsJLhk5oPk2CMFukWh+kb59JJai 045rWEZ6kG2gcJVsc8FP6Lm+KK0GJoIXEJ+/+CyJdQEKPhG2K9GXJTd7AAToOZ9EYx/62ZuOwD TDie4WsNBl5xyMVMWZJ5NC5ilhQoftQVo6zvnWoa/+uOxDkxJiBWrtD9hGnnlxvMg495+6RUiD dE0= X-IronPort-AV: E=Sophos;i="5.78,396,1599494400"; d="scan'208";a="258231903" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 06 Dec 2020 09:36:42 +0800 IronPort-SDR: 1QqOH88dxBDHK/0xhCPuAJ0zBDrsTYd6fVbA/30it+RHMhxMkqWO8DH1Uqeg2FabJzUXiXOSel qqRT5CQQCIaO64T217akLMGQ5GpgGNVuM= Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2020 17:02:28 -0800 IronPort-SDR: GVJjr/XO7KZ2n7w4nAwq5Yy4dpwjva5Zx+whwDQDJjV0M5rxNY9UFAuLNCLXvh6d7gbeALk5HV hs0Zmn1DeOcw== WDCIronportException: Internal Received: from cnf005296.ad.shared (HELO twashi.fujisawa.hgst.com) ([10.84.71.167]) by uls-op-cesaip02.wdc.com with ESMTP; 05 Dec 2020 17:18:23 -0800 From: Damien Le Moal To: Serge Semin , Mark Brown , linux-spi@vger.kernel.org, Rob Herring , devicetree@vger.kernel.org Cc: Sean Anderson Subject: [PATCH v3 2/3] spi: dw: Add support for 32-bits max xfer size Date: Sun, 6 Dec 2020 10:18:16 +0900 Message-Id: <20201206011817.11700-3-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201206011817.11700-1-damien.lemoal@wdc.com> References: <20201206011817.11700-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org The Synopsis DesignWare DW_apb_ssi specifications version 3.23 onward define a 32-bits maximum transfer size synthesis parameter (SSI_MAX_XFER_SIZE=32) in addition to the legacy 16-bits configuration (SSI_MAX_XFER_SIZE=16) for SPI controllers. When SSI_MAX_XFER_SIZE=32, the layout of the ctrlr0 register changes, moving the data frame format field from bits [3..0] to bits [16..20], and the RX/TX FIFO word size can be up to 32-bits. To support this new format, introduce the DW SPI capability flag DW_SPI_CAP_DFS32 to indicate that a controller is configured with SSI_MAX_XFER_SIZE=32. Since SSI_MAX_XFER_SIZE is a controller synthesis parameter not accessible through a register, the detection of this parameter value is done in spi_hw_init() by writing and reading the ctrlr0 register and testing the value of bits [3..0]. These bits are ignored (unchanged) for SSI_MAX_XFER_SIZE=16, allowing the detection. If a DFS32 capable SPI controller is detected, the new field dfs_offset in struct dw_spi is set to SPI_DFS32_OFFSET (16). dw_spi_update_config() is modified to set the data frame size field at the correct position is the CTRLR0 register, as indicated by the dfs_offset field of the dw_spi structure. The DW_SPI_CAP_DFS32 flag is also unconditionally set for SPI slave controllers, e.g. controllers that have the DW_SPI_CAP_DWC_SSI capability flag set. However, for these ssi controllers, the dfs_offset field is set to 0 as before (as per specifications). Finally, for any controller with the DW_SPI_CAP_DFS32 capability flag set, dw_spi_add_host() extends the value of bits_per_word_mask from 16-bits to 32-bits. dw_reader() and dw_writer() are also modified to handle 32-bits iTX/RX FIFO words. Suggested-by: Sean Anderson Signed-off-by: Damien Le Moal Acked-by: Serge Semin --- drivers/spi/spi-dw-core.c | 44 ++++++++++++++++++++++++++++++++------- drivers/spi/spi-dw.h | 5 +++++ 2 files changed, 42 insertions(+), 7 deletions(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index c33866f747db..a305074c482e 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -137,14 +137,16 @@ static inline u32 rx_max(struct dw_spi *dws) static void dw_writer(struct dw_spi *dws) { u32 max = tx_max(dws); - u16 txw = 0; + u32 txw = 0; while (max--) { if (dws->tx) { if (dws->n_bytes == 1) txw = *(u8 *)(dws->tx); - else + else if (dws->n_bytes == 2) txw = *(u16 *)(dws->tx); + else + txw = *(u32 *)(dws->tx); dws->tx += dws->n_bytes; } @@ -156,15 +158,17 @@ static void dw_writer(struct dw_spi *dws) static void dw_reader(struct dw_spi *dws) { u32 max = rx_max(dws); - u16 rxw; + u32 rxw; while (max--) { rxw = dw_read_io_reg(dws, DW_SPI_DR); if (dws->rx) { if (dws->n_bytes == 1) *(u8 *)(dws->rx) = rxw; - else + else if (dws->n_bytes == 2) *(u16 *)(dws->rx) = rxw; + else + *(u32 *)(dws->rx) = rxw; dws->rx += dws->n_bytes; } @@ -311,8 +315,8 @@ void dw_spi_update_config(struct dw_spi *dws, struct spi_device *spi, u32 speed_hz; u16 clk_div; - /* CTRLR0[ 4/3: 0] Data Frame Size */ - cr0 |= (cfg->dfs - 1); + /* CTRLR0[ 4/3: 0] or CTRLR0[ 20: 16] Data Frame Size */ + cr0 |= (cfg->dfs - 1) << dws->dfs_offset; if (!(dws->caps & DW_SPI_CAP_DWC_SSI)) /* CTRLR0[ 9:8] Transfer Mode */ @@ -828,6 +832,29 @@ static void spi_hw_init(struct device *dev, struct dw_spi *dws) dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len); } + /* + * Detect CTRLR0.DFS field size and offset by testing the lowest bits + * writability. Note DWC SSI controller also has the extended DFS, but + * with zero offset. + */ + if (!(dws->caps & DW_SPI_CAP_DWC_SSI)) { + u32 cr0, tmp = dw_readl(dws, DW_SPI_CTRLR0); + + spi_enable_chip(dws, 0); + dw_writel(dws, DW_SPI_CTRLR0, 0xffffffff); + cr0 = dw_readl(dws, DW_SPI_CTRLR0); + dw_writel(dws, DW_SPI_CTRLR0, tmp); + spi_enable_chip(dws, 1); + + if (!(cr0 & SPI_DFS_MASK)) { + dws->caps |= DW_SPI_CAP_DFS32; + dws->dfs_offset = SPI_DFS32_OFFSET; + dev_dbg(dev, "Detected 32-bits max data frame size\n"); + } + } else { + dws->caps |= DW_SPI_CAP_DFS32; + } + /* enable HW fixup for explicit CS deselect for Amazon's alpine chip */ if (dws->caps & DW_SPI_CAP_CS_OVERRIDE) dw_writel(dws, DW_SPI_CS_OVERRIDE, 0xF); @@ -864,7 +891,10 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) master->use_gpio_descriptors = true; master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP; - master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); + if (dws->caps & DW_SPI_CAP_DFS32) + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); + else + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); master->bus_num = dws->bus_num; master->num_chipselect = dws->num_cs; master->setup = dw_spi_setup; diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h index faf40cb66498..b665e040862c 100644 --- a/drivers/spi/spi-dw.h +++ b/drivers/spi/spi-dw.h @@ -9,6 +9,7 @@ #include #include #include +#include /* Register offsets */ #define DW_SPI_CTRLR0 0x00 @@ -41,6 +42,8 @@ /* Bit fields in CTRLR0 */ #define SPI_DFS_OFFSET 0 +#define SPI_DFS_MASK GENMASK(3, 0) +#define SPI_DFS32_OFFSET 16 #define SPI_FRF_OFFSET 4 #define SPI_FRF_SPI 0x0 @@ -121,6 +124,7 @@ enum dw_ssi_type { #define DW_SPI_CAP_CS_OVERRIDE BIT(0) #define DW_SPI_CAP_KEEMBAY_MST BIT(1) #define DW_SPI_CAP_DWC_SSI BIT(2) +#define DW_SPI_CAP_DFS32 BIT(3) /* Slave spi_transfer/spi_mem_op related */ struct dw_spi_cfg { @@ -148,6 +152,7 @@ struct dw_spi { unsigned long paddr; int irq; u32 fifo_len; /* depth of the FIFO buffer */ + unsigned int dfs_offset; /* CTRLR0 DFS field offset */ u32 max_mem_freq; /* max mem-ops bus freq */ u32 max_freq; /* max bus freq supported */ From patchwork Sun Dec 6 01:18:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 338971 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 440CFC4361B for ; Sun, 6 Dec 2020 01:20:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0FAE323128 for ; Sun, 6 Dec 2020 01:20:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726488AbgLFBUt (ORCPT ); Sat, 5 Dec 2020 20:20:49 -0500 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:35643 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726037AbgLFBUt (ORCPT ); Sat, 5 Dec 2020 20:20:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1607218820; x=1638754820; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FUFns0ZQm6ox08bIyStAPeZebNJokqWZzdgTWJBkH6w=; b=T1GrqXZ0ttokYT5b0iLgGAzY1dLYVaYNvwlK3LR8mGh5jIk6mebQpmG2 REkKpk+RQWR3Zaar9J575tYj7oCW6LYADXs+++cbTEupoi4aroyktnWrG xB2aNNQJvWMb7tSoBJIpOJEOPAL3cC2nEH5Rr2ri7Jlg00jh1+yLEp8Jc hLko4vjqFbWVGkby/CsJFp6thL8twd/uD3ns0Ue1SJ/jISg1kQoyqozOw bSZuzgd5LjQIpqvB14Suaf5UiSu1RRI7gxCkUeTF9aQBAVFNgrd0u2e+5 PgRfduJDOqNgvWXdmhaVHKp7rtH26JOuf1cak/h+3UzLmBhnyGOv+pPtB g==; IronPort-SDR: Xvl+jzFNmQ1BhSDjoBxWZdYhWOrIO0Y5leckQskfZYiA4+7LIGLOihX6Y86Xrljbs2X7q4ytPo R+qudSrtd0lrrCg+ff2BOODx+D8zQVA5RfszzXkIcweXh5j8G4wS1Xn6EGM2/Ecq8VUScIa73O YAIMfdTCByNzp5BNt+AkiUSfnZHw8Y4dT52tsVuusbu2+rd61m/dVQngU5CxLjx1dlrPmXLljE E/V2smkT9EJExcX/Vdh6MGpZwcevu1SAThCkpAYZBck3zYOUCQ1pGFfTE883hlFgPIb4ru5WlG QME= X-IronPort-AV: E=Sophos;i="5.78,396,1599494400"; d="scan'208";a="258231905" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 06 Dec 2020 09:36:44 +0800 IronPort-SDR: VHqc6V4J5mKOzVaT0nfeV62jmeRMy/S6E8Rw2cjh48KsVili7ATpBALB5tfKRZq7QuPgkfZzHa 2y728DYB5KwstQ8+TZNJDQ5d2sizwvfOc= Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2020 17:02:29 -0800 IronPort-SDR: iuWzoU0omr+w0WQH3pDr3M7C60JKNycOEC1/dNQb4ANbT3xn8NsPY451TXb5NdMjeCwodITQkg 3VMgVaMMzETw== WDCIronportException: Internal Received: from cnf005296.ad.shared (HELO twashi.fujisawa.hgst.com) ([10.84.71.167]) by uls-op-cesaip02.wdc.com with ESMTP; 05 Dec 2020 17:18:24 -0800 From: Damien Le Moal To: Serge Semin , Mark Brown , linux-spi@vger.kernel.org, Rob Herring , devicetree@vger.kernel.org Cc: Sean Anderson Subject: [PATCH v3 3/3] spi: dw: Add support for the Canaan K210 SoC SPI Date: Sun, 6 Dec 2020 10:18:17 +0900 Message-Id: <20201206011817.11700-4-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201206011817.11700-1-damien.lemoal@wdc.com> References: <20201206011817.11700-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org The Canaan Kendryte K210 RISC-V SoC includes a DW apb_ssi v4 controller which is documented to have a 32 words deep TX and RX FIFO. The FIFO length detection in spi_hw_init() correctly detects this value. However, when the controller RX FIFO is filled up to 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. This likely due to a hardware bug which can be avoided by force setting the fifo_len field of struct dw_spi to 31. Define the dw_spi_canaan_k210_init() function to force set fifo_len to 31 when the device node compatible string is "canaan,k210-spi". Signed-off-by: Damien Le Moal Acked-by: Serge Semin --- drivers/spi/spi-dw-mmio.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index d0cc5bf4fa4e..17c06039a74d 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -222,6 +222,21 @@ static int dw_spi_keembay_init(struct platform_device *pdev, return 0; } +static int dw_spi_canaan_k210_init(struct platform_device *pdev, + struct dw_spi_mmio *dwsmmio) +{ + /* + * The Canaan Kendryte K210 SoC DW apb_ssi v4 spi controller is + * documented to have a 32 word deep TX and RX FIFO, which + * spi_hw_init() detects. However, when the RX FIFO is filled up to + * 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. Avoid this + * problem by force setting fifo_len to 31. + */ + dwsmmio->dws.fifo_len = 31; + + return 0; +} + static int dw_spi_mmio_probe(struct platform_device *pdev) { int (*init_func)(struct platform_device *pdev, @@ -335,6 +350,7 @@ static const struct of_device_id dw_spi_mmio_of_match[] = { { .compatible = "snps,dwc-ssi-1.01a", .data = dw_spi_dwc_ssi_init}, { .compatible = "intel,keembay-ssi", .data = dw_spi_keembay_init}, { .compatible = "microchip,sparx5-spi", dw_spi_mscc_sparx5_init}, + { .compatible = "canaan,k210-spi", dw_spi_canaan_k210_init}, { /* end of table */} }; MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);