From patchwork Wed Nov 22 09:27:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Binbin Zhou X-Patchwork-Id: 13464317 Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E9AEC19E; Wed, 22 Nov 2023 01:27:27 -0800 (PST) Received: from loongson.cn (unknown [112.20.112.120]) by gateway (Coremail) with SMTP id _____8Cxh+h+yV1lhuM7AA--.17387S3; Wed, 22 Nov 2023 17:27:26 +0800 (CST) Received: from localhost.localdomain (unknown [112.20.112.120]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Bx3y92yV1lMF5JAA--.31241S3; Wed, 22 Nov 2023 17:27:23 +0800 (CST) From: Binbin Zhou To: Binbin Zhou , Huacai Chen , Vinod Koul , dmaengine@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , devicetree@vger.kernel.org Cc: Huacai Chen , loongson-kernel@lists.loongnix.cn, Xuerui Wang , loongarch@lists.linux.dev, Yingkun Meng , Binbin Zhou , Conor Dooley Subject: [PATCH v5 1/2] dt-bindings: dmaengine: Add Loongson LS2X APB DMA controller Date: Wed, 22 Nov 2023 17:27:10 +0800 Message-Id: <297682e04280b062c159ba95765360e61c45b2a4.1700644483.git.zhoubinbin@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8Bx3y92yV1lMF5JAA--.31241S3 X-CM-SenderInfo: p2kr3uplqex0o6or00hjvr0hdfq/ X-Coremail-Antispam: 1Uk129KBj93XoWxZw4kZr47Ar15Zw4UZF1xCrX_yoW5Xr17pF nxC3ZxKrW0qF17A395JFy0k3WfZ3s3A3ZrWa9rAwnrKrZ8X3ZYvw4akr1vvay3CrWjqFW7 ZFZa9r4jka4xArcCm3ZEXasCq-sJn29KB7ZKAUJUUUUx529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUBIb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2kKe7AKxVWUAVWUtwAS0I0E0xvYzxvE52x082IY62kv0487Mc804VCY07 AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU tVWrXwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7V AKI48JMxkF7I0En4kS14v26r126r1DMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY 6r1j6r4UMxCIbckI1I0E14v26r126r1DMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7 xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xII jxv20xvE14v26r4j6ryUMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw2 0EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x02 67AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU8_gA5UUUUU== Add Loongson LS2X APB DMA controller binding with DT schema format using json-schema. Signed-off-by: Binbin Zhou Reviewed-by: Conor Dooley --- .../bindings/dma/loongson,ls2x-apbdma.yaml | 62 +++++++++++++++++++ MAINTAINERS | 6 ++ 2 files changed, 68 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/loongson,ls2x-apbdma.yaml diff --git a/Documentation/devicetree/bindings/dma/loongson,ls2x-apbdma.yaml b/Documentation/devicetree/bindings/dma/loongson,ls2x-apbdma.yaml new file mode 100644 index 000000000000..35298c4fbfa0 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/loongson,ls2x-apbdma.yaml @@ -0,0 +1,62 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/dma/loongson,ls2x-apbdma.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Loongson LS2X APB DMA controller + +description: + The Loongson LS2X APB DMA controller is used for transferring data + between system memory and the peripherals on the APB bus. + +maintainers: + - Binbin Zhou + +allOf: + - $ref: dma-controller.yaml# + +properties: + compatible: + oneOf: + - const: loongson,ls2k1000-apbdma + - items: + - const: loongson,ls2k0500-apbdma + - const: loongson,ls2k1000-apbdma + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + clocks: + maxItems: 1 + + '#dma-cells': + const: 1 + +required: + - compatible + - reg + - interrupts + - clocks + - '#dma-cells' + +additionalProperties: false + +examples: + - | + #include + #include + + dma-controller@1fe00c00 { + compatible = "loongson,ls2k1000-apbdma"; + reg = <0x1fe00c00 0x8>; + interrupt-parent = <&liointc1>; + interrupts = <12 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&clk LOONGSON2_APB_CLK>; + #dma-cells = <1>; + }; + +... diff --git a/MAINTAINERS b/MAINTAINERS index 3e3206dc1672..eb1d9c4f85d0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12506,6 +12506,12 @@ S: Maintained F: Documentation/devicetree/bindings/gpio/loongson,ls-gpio.yaml F: drivers/gpio/gpio-loongson-64bit.c +LOONGSON LS2X APB DMA DRIVER +M: Binbin Zhou +L: dmaengine@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/dma/loongson,ls2x-apbdma.yaml + LOONGSON LS2X I2C DRIVER M: Binbin Zhou L: linux-i2c@vger.kernel.org From patchwork Wed Nov 22 09:27:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Binbin Zhou X-Patchwork-Id: 13464318 Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D4C57F9; Wed, 22 Nov 2023 01:27:30 -0800 (PST) Received: from loongson.cn (unknown [112.20.112.120]) by gateway (Coremail) with SMTP id _____8DxqOqAyV1ljuM7AA--.17359S3; Wed, 22 Nov 2023 17:27:28 +0800 (CST) Received: from localhost.localdomain (unknown [112.20.112.120]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Bx3y92yV1lMF5JAA--.31241S4; Wed, 22 Nov 2023 17:27:27 +0800 (CST) From: Binbin Zhou To: Binbin Zhou , Huacai Chen , Vinod Koul , dmaengine@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , devicetree@vger.kernel.org Cc: Huacai Chen , loongson-kernel@lists.loongnix.cn, Xuerui Wang , loongarch@lists.linux.dev, Yingkun Meng , Binbin Zhou Subject: [PATCH v5 2/2] dmaengine: ls2x-apb: new driver for the Loongson LS2X APB DMA controller Date: Wed, 22 Nov 2023 17:27:11 +0800 Message-Id: <00ca551194a5ee69840b1a1a556d7b954153f455.1700644483.git.zhoubinbin@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8Bx3y92yV1lMF5JAA--.31241S4 X-CM-SenderInfo: p2kr3uplqex0o6or00hjvr0hdfq/ X-Coremail-Antispam: 1Uk129KBj9fXoWfXFy3WryfXw4UJryxCr1Dtwc_yoW8KFyUJo Z3urs3ur4rJw1UXrWIgr1DKFW7ZF1I9wn5A34rJrs09a1DZF1Yka4UCrn8Wa4ftr13KayU C3saqwnruF4xZF4rl-sFpf9Il3svdjkaLaAFLSUrUUUU8b8apTn2vfkv8UJUUUU8wcxFpf 9Il3svdxBIdaVrn0xqx4xG64xvF2IEw4CE5I8CrVC2j2Jv73VFW2AGmfu7bjvjm3AaLaJ3 UjIYCTnIWjp_UUUYC7kC6x804xWl14x267AKxVWUJVW8JwAFc2x0x2IEx4CE42xK8VAvwI 8IcIk0rVWrJVCq3wAFIxvE14AKwVWUXVWUAwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xG Y2AK021l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14 v26r4j6F4UM28EF7xvwVC2z280aVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIEc7CjxVAF wI0_Gr1j6F4UJwAaw2AFwI0_Jrv_JF1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqjxCEc2 xF0cIa020Ex4CE44I27wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_ Jw0_WrylYx0Ex4A2jsIE14v26r4j6F4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x 0EwIxGrwCY1x0262kKe7AKxVWUAVWUtwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwCFI7km07C267AKxVWUXVWUAwC20s026c02F40E14v26r1j6r18MI8I3I0E74 80Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0 I7IYx2IY67AKxVW8JVW5JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04 k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r4j6F4UMIIF0xvEx4A2jsIEc7Cj xVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07j2MKZUUUUU= The Loongson LS2X APB DMA controller is available on Loongson-2K chips. It is a single-channel, configurable DMA controller IP core based on the AXI bus, whose main function is to integrate DMA functionality on a chip dedicated to carrying data between memory and peripherals in APB bus (e.g. nand). Signed-off-by: Binbin Zhou Signed-off-by: Yingkun Meng --- MAINTAINERS | 1 + drivers/dma/Kconfig | 14 + drivers/dma/Makefile | 1 + drivers/dma/ls2x-apb-dma.c | 705 +++++++++++++++++++++++++++++++++++++ 4 files changed, 721 insertions(+) create mode 100644 drivers/dma/ls2x-apb-dma.c diff --git a/MAINTAINERS b/MAINTAINERS index eb1d9c4f85d0..6b8d7f5b241b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12511,6 +12511,7 @@ M: Binbin Zhou L: dmaengine@vger.kernel.org S: Maintained F: Documentation/devicetree/bindings/dma/loongson,ls2x-apbdma.yaml +F: drivers/dma/ls2x-apb-dma.c LOONGSON LS2X I2C DRIVER M: Binbin Zhou diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 70ba506dabab..e928f2ca0f1e 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -378,6 +378,20 @@ config LPC18XX_DMAMUX Enable support for DMA on NXP LPC18xx/43xx platforms with PL080 and multiplexed DMA request lines. +config LS2X_APB_DMA + tristate "Loongson LS2X APB DMA support" + depends on LOONGARCH || COMPILE_TEST + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + Support for the Loongson LS2X APB DMA controller driver. The + DMA controller is having single DMA channel which can be + configured for different peripherals like audio, nand, sdio + etc which is in APB bus. + + This DMA controller transfers data from memory to peripheral fifo. + It does not support memory to memory data transfer. + config MCF_EDMA tristate "Freescale eDMA engine support, ColdFire mcf5441x SoCs" depends on M5441x || COMPILE_TEST diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index 83553a97a010..dfd40d14e408 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_INTEL_IOATDMA) += ioat/ obj-y += idxd/ obj-$(CONFIG_K3_DMA) += k3dma.o obj-$(CONFIG_LPC18XX_DMAMUX) += lpc18xx-dmamux.o +obj-$(CONFIG_LS2X_APB_DMA) += ls2x-apb-dma.o obj-$(CONFIG_MILBEAUT_HDMAC) += milbeaut-hdmac.o obj-$(CONFIG_MILBEAUT_XDMAC) += milbeaut-xdmac.o obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o diff --git a/drivers/dma/ls2x-apb-dma.c b/drivers/dma/ls2x-apb-dma.c new file mode 100644 index 000000000000..f60dbeae627f --- /dev/null +++ b/drivers/dma/ls2x-apb-dma.c @@ -0,0 +1,705 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for the Loongson LS2X APB DMA Controller + * + * Copyright (C) 2017-2023 Loongson Corporation + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "dmaengine.h" +#include "virt-dma.h" + +/* Global Configuration Register */ +#define LDMA_ORDER_ERG 0x0 + +/* Bitfield definitions */ + +/* Bitfields in Global Configuration Register */ +#define LDMA_64BIT_EN BIT(0) /* 1: 64 bit support */ +#define LDMA_UNCOHERENT_EN BIT(1) /* 0: cache, 1: uncache */ +#define LDMA_ASK_VALID BIT(2) +#define LDMA_START BIT(3) /* DMA start operation */ +#define LDMA_STOP BIT(4) /* DMA stop operation */ +#define LDMA_CONFIG_MASK GENMASK(4, 0) /* DMA controller config bits mask */ + +/* Bitfields in ndesc_addr field of HW decriptor */ +#define LDMA_DESC_EN BIT(0) /*1: The next descriptor is valid */ +#define LDMA_DESC_ADDR_LOW GENMASK(31, 1) + +/* Bitfields in cmd field of HW decriptor */ +#define LDMA_INT BIT(1) /* Enable DMA interrupts */ +#define LDMA_DATA_DIRECTION BIT(12) /* 1: write to device, 0: read from device */ + +#define LDMA_SLAVE_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)) + +#define LDMA_MAX_TRANS_LEN U32_MAX + +/*-- descriptors -----------------------------------------------------*/ + +/* + * struct ls2x_dma_hw_desc - DMA HW descriptor + * @ndesc_addr: the next descriptor low address. + * @mem_addr: memory low address. + * @apb_addr: device buffer address. + * @len: length of a piece of carried content, in words. + * @step_len: length between two moved memory data blocks. + * @step_times: number of blocks to be carried in a single DMA operation. + * @cmd: descriptor command or state. + * @stats: DMA status. + * @high_ndesc_addr: the next descriptor high address. + * @high_mem_addr: memory high address. + * @reserved: reserved + */ +struct ls2x_dma_hw_desc { + u32 ndesc_addr; + u32 mem_addr; + u32 apb_addr; + u32 len; + u32 step_len; + u32 step_times; + u32 cmd; + u32 stats; + u32 high_ndesc_addr; + u32 high_mem_addr; + u32 reserved[2]; +} __packed; + +/* + * struct ls2x_dma_sg - ls2x dma scatter gather entry + * @hw: the pointer to DMA HW descriptor. + * @llp: physical address of the DMA HW descriptor. + * @phys: destination or source address(mem). + * @len: number of Bytes to read. + */ +struct ls2x_dma_sg { + struct ls2x_dma_hw_desc *hw; + dma_addr_t llp; + dma_addr_t phys; + u32 len; +}; + +/* + * struct ls2x_dma_desc - software descriptor + * @vdesc: pointer to the virtual dma descriptor. + * @cyclic: flag to dma cyclic + * @burst_size: burst size of transaction, in words. + * @desc_num: number of sg entries. + * @direction: transfer direction, to or from device. + * @status: dma controller status. + * @sg: array of sgs. + */ +struct ls2x_dma_desc { + struct virt_dma_desc vdesc; + bool cyclic; + size_t burst_size; + u32 desc_num; + enum dma_transfer_direction direction; + enum dma_status status; + struct ls2x_dma_sg sg[] __counted_by(desc_num); +}; + +/*-- Channels --------------------------------------------------------*/ + +/* + * struct ls2x_dma_chan - internal representation of an LS2X APB DMA channel + * @vchan: virtual dma channel entry. + * @desc: pointer to the ls2x sw dma descriptor. + * @pool: hw desc table + * @irq: irq line + * @sconfig: configuration for slave transfers, passed via .device_config + */ +struct ls2x_dma_chan { + struct virt_dma_chan vchan; + struct ls2x_dma_desc *desc; + void *pool; + int irq; + struct dma_slave_config sconfig; +}; + +/*-- Controller ------------------------------------------------------*/ + +/* + * struct ls2x_dma_priv - LS2X APB DMAC specific information + * @ddev: dmaengine dma_device object members + * @dma_clk: DMAC clock source + * @regs: memory mapped register base + * @lchan: channel to store ls2x_dma_chan structures + */ +struct ls2x_dma_priv { + struct dma_device ddev; + struct clk *dma_clk; + void __iomem *regs; + struct ls2x_dma_chan lchan; +}; + +/*-- Helper functions ------------------------------------------------*/ + +static inline struct ls2x_dma_desc *to_ldma_desc(struct virt_dma_desc *vdesc) +{ + return container_of(vdesc, struct ls2x_dma_desc, vdesc); +} + +static inline struct ls2x_dma_chan *to_ldma_chan(struct dma_chan *chan) +{ + return container_of(chan, struct ls2x_dma_chan, vchan.chan); +} + +static inline struct ls2x_dma_priv *to_ldma_priv(struct dma_device *ddev) +{ + return container_of(ddev, struct ls2x_dma_priv, ddev); +} + +static struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} + +static void ls2x_dma_desc_free(struct virt_dma_desc *vdesc) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(vdesc->tx.chan); + struct ls2x_dma_desc *desc = to_ldma_desc(vdesc); + int i; + + for (i = 0; i < desc->desc_num; i++) { + if (desc->sg[i].hw) + dma_pool_free(lchan->pool, desc->sg[i].hw, + desc->sg[i].llp); + } + + kfree(desc); +} + +static void ls2x_dma_write_cmd(struct ls2x_dma_chan *lchan, bool cmd) +{ + u64 val = 0; + struct ls2x_dma_priv *priv = to_ldma_priv(lchan->vchan.chan.device); + + val = lo_hi_readq(priv->regs + LDMA_ORDER_ERG) & ~LDMA_CONFIG_MASK; + val |= LDMA_64BIT_EN | cmd; + lo_hi_writeq(val, priv->regs + LDMA_ORDER_ERG); +} + +static void ls2x_dma_start_transfer(struct ls2x_dma_chan *lchan) +{ + struct ls2x_dma_priv *priv = to_ldma_priv(lchan->vchan.chan.device); + struct ls2x_dma_sg *ldma_sg; + struct virt_dma_desc *vdesc; + u64 val; + + /* Get the next descriptor */ + vdesc = vchan_next_desc(&lchan->vchan); + if (!vdesc) { + lchan->desc = NULL; + return; + } + + list_del(&vdesc->node); + lchan->desc = to_ldma_desc(vdesc); + ldma_sg = &lchan->desc->sg[0]; + + /* Start DMA */ + lo_hi_writeq(0, priv->regs + LDMA_ORDER_ERG); + val = (ldma_sg->llp & ~LDMA_CONFIG_MASK) | LDMA_64BIT_EN | LDMA_START; + lo_hi_writeq(val, priv->regs + LDMA_ORDER_ERG); +} + +static size_t ls2x_dmac_detect_burst(struct ls2x_dma_chan *lchan) +{ + u32 maxburst, buswidth; + + /* Reject definitely invalid configurations */ + if ((lchan->sconfig.src_addr_width & LDMA_SLAVE_BUSWIDTHS) && + (lchan->sconfig.dst_addr_width & LDMA_SLAVE_BUSWIDTHS)) + return 0; + + if (lchan->sconfig.direction == DMA_MEM_TO_DEV) { + maxburst = lchan->sconfig.dst_maxburst; + buswidth = lchan->sconfig.dst_addr_width; + } else { + maxburst = lchan->sconfig.src_maxburst; + buswidth = lchan->sconfig.src_addr_width; + } + + /* If maxburst is zero, fallback to LDMA_MAX_TRANS_LEN */ + return maxburst ? (maxburst * buswidth) >> 2 : LDMA_MAX_TRANS_LEN; +} + +static void ls2x_dma_fill_desc(struct ls2x_dma_chan *lchan, u32 sg_index, + struct ls2x_dma_desc *desc) +{ + struct ls2x_dma_sg *ldma_sg = &desc->sg[sg_index]; + u32 num_segments, segment_size; + + if (desc->direction == DMA_MEM_TO_DEV) { + ldma_sg->hw->cmd = LDMA_INT | LDMA_DATA_DIRECTION; + ldma_sg->hw->apb_addr = lchan->sconfig.dst_addr; + } else { + ldma_sg->hw->cmd = LDMA_INT; + ldma_sg->hw->apb_addr = lchan->sconfig.src_addr; + } + + ldma_sg->hw->mem_addr = lower_32_bits(ldma_sg->phys); + ldma_sg->hw->high_mem_addr = upper_32_bits(ldma_sg->phys); + + /* Split into multiple equally sized segments if necessary */ + num_segments = DIV_ROUND_UP((ldma_sg->len + 3) >> 2, desc->burst_size); + segment_size = DIV_ROUND_UP((ldma_sg->len + 3) >> 2, num_segments); + + /* Word count register takes input in words */ + ldma_sg->hw->len = segment_size; + ldma_sg->hw->step_times = num_segments; + ldma_sg->hw->step_len = 0; + + /* lets make a link list */ + if (sg_index) { + desc->sg[sg_index - 1].hw->ndesc_addr = ldma_sg->llp | LDMA_DESC_EN; + desc->sg[sg_index - 1].hw->high_ndesc_addr = upper_32_bits(ldma_sg->llp); + } +} + +/*-- DMA Engine API --------------------------------------------------*/ + +/* + * ls2x_dma_alloc_chan_resources - allocate resources for DMA channel + * @chan: allocate descriptor resources for this channel + * + * return - the number of allocated descriptors + */ +static int ls2x_dma_alloc_chan_resources(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + /* Create a pool of consistent memory blocks for hardware descriptors */ + lchan->pool = dma_pool_create(dev_name(chan2dev(chan)), + chan->device->dev, PAGE_SIZE, + __alignof__(struct ls2x_dma_hw_desc), 0); + if (!lchan->pool) { + dev_err(chan2dev(chan), "No memory for descriptors\n"); + return -ENOMEM; + } + + return 1; +} + +/* + * ls2x_dma_free_chan_resources - free all channel resources + * @chan: DMA channel + */ +static void ls2x_dma_free_chan_resources(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + vchan_free_chan_resources(to_virt_chan(chan)); + dma_pool_destroy(lchan->pool); + lchan->pool = NULL; +} + +/* + * ls2x_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction + * @chan: DMA channel + * @sgl: scatterlist to transfer to/from + * @sg_len: number of entries in @scatterlist + * @direction: DMA direction + * @flags: tx descriptor status flags + * @context: transaction context (ignored) + * + * Return: Async transaction descriptor on success and NULL on failure + */ +static struct dma_async_tx_descriptor * +ls2x_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, + u32 sg_len, enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + struct ls2x_dma_desc *desc; + struct scatterlist *sg; + size_t burst_size; + int i; + + if (unlikely(!sg_len || !is_slave_direction(direction))) + return NULL; + + burst_size = ls2x_dmac_detect_burst(lchan); + if (!burst_size) + return NULL; + + desc = kzalloc(struct_size(desc, sg, sg_len), GFP_ATOMIC); + if (!desc) + return NULL; + + desc->desc_num = sg_len; + desc->direction = direction; + desc->burst_size = burst_size; + + for_each_sg(sgl, sg, sg_len, i) { + struct ls2x_dma_sg *ldma_sg = &desc->sg[i]; + + /* Allocate DMA capable memory for hardware descriptor */ + ldma_sg->hw = dma_pool_alloc(lchan->pool, GFP_NOWAIT, &ldma_sg->llp); + if (!ldma_sg->hw) { + desc->desc_num = i; + ls2x_dma_desc_free(&desc->vdesc); + return NULL; + } + + ldma_sg->phys = sg_dma_address(sg); + ldma_sg->len = sg_dma_len(sg); + + ls2x_dma_fill_desc(lchan, i, desc); + } + + /* Setting the last descriptor enable bit */ + desc->sg[sg_len - 1].hw->ndesc_addr &= ~LDMA_DESC_EN; + desc->status = DMA_IN_PROGRESS; + + return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags); +} + +/* + * ls2x_dma_prep_dma_cyclic - prepare the cyclic DMA transfer + * @chan: the DMA channel to prepare + * @buf_addr: physical DMA address where the buffer starts + * @buf_len: total number of bytes for the entire buffer + * @period_len: number of bytes for each period + * @direction: transfer direction, to or from device + * @flags: tx descriptor status flags + * + * Return: Async transaction descriptor on success and NULL on failure + */ +static struct dma_async_tx_descriptor * +ls2x_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction direction, + unsigned long flags) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + struct ls2x_dma_desc *desc; + u32 num_periods; + size_t burst_size; + int i; + + if (unlikely(!buf_len || !period_len)) + return NULL; + + if (unlikely(!is_slave_direction(direction))) + return NULL; + + burst_size = ls2x_dmac_detect_burst(lchan); + if (!burst_size) + return NULL; + + num_periods = buf_len / period_len; + desc = kzalloc(struct_size(desc, sg, num_periods), GFP_ATOMIC); + if (!desc) + return NULL; + + desc->desc_num = num_periods; + desc->direction = direction; + desc->burst_size = burst_size; + + /* Build cyclic linked list */ + for (i = 0; i < num_periods; i++) { + struct ls2x_dma_sg *ldma_sg = &desc->sg[i]; + + /* Allocate DMA capable memory for hardware descriptor */ + ldma_sg->hw = dma_pool_alloc(lchan->pool, GFP_NOWAIT, &ldma_sg->llp); + if (!ldma_sg->hw) { + desc->desc_num = i; + ls2x_dma_desc_free(&desc->vdesc); + return NULL; + } + + ldma_sg->phys = buf_addr + period_len * i; + ldma_sg->len = period_len; + + ls2x_dma_fill_desc(lchan, i, desc); + } + + /* Lets make a cyclic list */ + desc->sg[num_periods - 1].hw->ndesc_addr = desc->sg[0].llp | LDMA_DESC_EN; + desc->sg[num_periods - 1].hw->high_ndesc_addr = upper_32_bits(desc->sg[0].llp); + desc->cyclic = true; + desc->status = DMA_IN_PROGRESS; + + return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags); +} + +/* + * ls2x_slave_config - set slave configuration for channel + * @chan: dma channel + * @cfg: slave configuration + * + * Sets slave configuration for channel + */ +static int ls2x_dma_slave_config(struct dma_chan *chan, + struct dma_slave_config *config) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + memcpy(&lchan->sconfig, config, sizeof(*config)); + return 0; +} + +/* + * ls2x_dma_issue_pending - push pending transactions to the hardware + * @chan: channel + * + * When this function is called, all pending transactions are pushed to the + * hardware and executed. + */ +static void ls2x_dma_issue_pending(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + unsigned long flags; + + spin_lock_irqsave(&lchan->vchan.lock, flags); + if (vchan_issue_pending(&lchan->vchan) && !lchan->desc) + ls2x_dma_start_transfer(lchan); + spin_unlock_irqrestore(&lchan->vchan.lock, flags); +} + +/* + * ls2x_dma_terminate_all - terminate all transactions + * @chan: channel + * + * Stops all DMA transactions. + */ +static int ls2x_dma_terminate_all(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&lchan->vchan.lock, flags); + /* Setting stop cmd */ + ls2x_dma_write_cmd(lchan, LDMA_STOP); + if (lchan->desc) { + vchan_terminate_vdesc(&lchan->desc->vdesc); + lchan->desc = NULL; + } + + vchan_get_all_descriptors(&lchan->vchan, &head); + spin_unlock_irqrestore(&lchan->vchan.lock, flags); + + vchan_dma_desc_free_list(&lchan->vchan, &head); + return 0; +} + +/* + * ls2x_dma_synchronize - Synchronizes the termination of transfers to the + * current context. + * @chan: channel + */ +static void ls2x_dma_synchronize(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + vchan_synchronize(&lchan->vchan); +} + +static int ls2x_dma_pause(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + unsigned long flags; + + spin_lock_irqsave(&lchan->vchan.lock, flags); + if (lchan->desc && lchan->desc->status == DMA_IN_PROGRESS) { + ls2x_dma_write_cmd(lchan, LDMA_STOP); + lchan->desc->status = DMA_PAUSED; + } + spin_unlock_irqrestore(&lchan->vchan.lock, flags); + + return 0; +} + +static int ls2x_dma_resume(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + unsigned long flags; + + spin_lock_irqsave(&lchan->vchan.lock, flags); + if (lchan->desc && lchan->desc->status == DMA_PAUSED) { + lchan->desc->status = DMA_IN_PROGRESS; + ls2x_dma_write_cmd(lchan, LDMA_START); + } + spin_unlock_irqrestore(&lchan->vchan.lock, flags); + + return 0; +} + +/* + * ls2x_dma_isr - LS2X DMA Interrupt handler + * @irq: IRQ number + * @dev_id: Pointer to ls2x_dma_chan + * + * Return: IRQ_HANDLED/IRQ_NONE + */ +static irqreturn_t ls2x_dma_isr(int irq, void *dev_id) +{ + struct ls2x_dma_chan *lchan = dev_id; + struct ls2x_dma_desc *desc; + + spin_lock(&lchan->vchan.lock); + desc = lchan->desc; + if (desc) { + if (desc->cyclic) { + vchan_cyclic_callback(&desc->vdesc); + } else { + desc->status = DMA_COMPLETE; + vchan_cookie_complete(&desc->vdesc); + ls2x_dma_start_transfer(lchan); + } + + /* ls2x_dma_start_transfer() updates lchan->desc */ + if (!lchan->desc) + ls2x_dma_write_cmd(lchan, LDMA_STOP); + } + spin_unlock(&lchan->vchan.lock); + + return IRQ_HANDLED; +} + +static int ls2x_dma_chan_init(struct platform_device *pdev, + struct ls2x_dma_priv *priv) +{ + struct device *dev = &pdev->dev; + struct ls2x_dma_chan *lchan = &priv->lchan; + int ret; + + lchan->irq = platform_get_irq(pdev, 0); + if (lchan->irq < 0) + return lchan->irq; + + ret = devm_request_irq(dev, lchan->irq, ls2x_dma_isr, IRQF_TRIGGER_RISING, + dev_name(&pdev->dev), lchan); + if (ret) + return ret; + + /* Initialize channels related values */ + INIT_LIST_HEAD(&priv->ddev.channels); + lchan->vchan.desc_free = ls2x_dma_desc_free; + vchan_init(&lchan->vchan, &priv->ddev); + + return 0; +} + +/* + * ls2x_dma_probe - Driver probe function + * @pdev: Pointer to the platform_device structure + * + * Return: '0' on success and failure value on error + */ +static int ls2x_dma_probe(struct platform_device *pdev) +{ + int ret; + struct dma_device *ddev; + struct ls2x_dma_priv *priv; + struct device *dev = &pdev->dev; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->regs)) + return dev_err_probe(dev, PTR_ERR(priv->regs), + "devm_platform_ioremap_resource failed.\n"); + + priv->dma_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(priv->dma_clk)) + return dev_err_probe(dev, PTR_ERR(priv->dma_clk), "devm_clk_get failed.\n"); + + ret = clk_prepare_enable(priv->dma_clk); + if (ret) + return dev_err_probe(dev, ret, "clk_prepare_enable failed.\n"); + + ret = ls2x_dma_chan_init(pdev, priv); + if (ret) + goto disable_clk; + + ddev = &priv->ddev; + ddev->dev = dev; + dma_cap_zero(ddev->cap_mask); + dma_cap_set(DMA_SLAVE, ddev->cap_mask); + dma_cap_set(DMA_CYCLIC, ddev->cap_mask); + + ddev->device_alloc_chan_resources = ls2x_dma_alloc_chan_resources; + ddev->device_free_chan_resources = ls2x_dma_free_chan_resources; + ddev->device_tx_status = dma_cookie_status; + ddev->device_issue_pending = ls2x_dma_issue_pending; + ddev->device_prep_slave_sg = ls2x_dma_prep_slave_sg; + ddev->device_prep_dma_cyclic = ls2x_dma_prep_dma_cyclic; + ddev->device_config = ls2x_dma_slave_config; + ddev->device_terminate_all = ls2x_dma_terminate_all; + ddev->device_synchronize = ls2x_dma_synchronize; + ddev->device_pause = ls2x_dma_pause; + ddev->device_resume = ls2x_dma_resume; + + ddev->src_addr_widths = LDMA_SLAVE_BUSWIDTHS; + ddev->dst_addr_widths = LDMA_SLAVE_BUSWIDTHS; + ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + + ret = dma_async_device_register(&priv->ddev); + if (ret < 0) + goto disable_clk; + + ret = of_dma_controller_register(dev->of_node, of_dma_xlate_by_chan_id, priv); + if (ret < 0) + goto unregister_dmac; + + platform_set_drvdata(pdev, priv); + + dev_info(dev, "Loongson LS2X APB DMA driver registered successfully.\n"); + return 0; + +unregister_dmac: + dma_async_device_unregister(&priv->ddev); +disable_clk: + clk_disable_unprepare(priv->dma_clk); + + return ret; +} + +/* + * ls2x_dma_remove - Driver remove function + * @pdev: Pointer to the platform_device structure + */ +static void ls2x_dma_remove(struct platform_device *pdev) +{ + struct ls2x_dma_priv *priv = platform_get_drvdata(pdev); + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&priv->ddev); + clk_disable_unprepare(priv->dma_clk); +} + +static const struct of_device_id ls2x_dma_of_match_table[] = { + { .compatible = "loongson,ls2k1000-apbdma" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, ls2x_dma_of_match_table); + +static struct platform_driver ls2x_dmac_driver = { + .probe = ls2x_dma_probe, + .remove_new = ls2x_dma_remove, + .driver = { + .name = "ls2x-apbdma", + .of_match_table = ls2x_dma_of_match_table, + }, +}; +module_platform_driver(ls2x_dmac_driver); + +MODULE_DESCRIPTION("Loongson LS2X APB DMA Controller driver"); +MODULE_AUTHOR("Loongson Technology Corporation Limited"); +MODULE_LICENSE("GPL");