Re: [PATCH v5 5/7] spi: spi-qpic: add driver for QCOM SPI NAND flash Interface

[Miquel Raynal]

Hi,

> --- /dev/null
> +++ b/drivers/spi/spi-qpic-snand.c
> @@ -0,0 +1,1423 @@
> +/*
> + * SPDX-License-Identifier: GPL-2.0
> + *
> + * Copyright (c) 2023, Qualcomm Innovation Center, Inc. All rights reserved.
> + *
> + * Authors:
> + *	Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>
> + *	Sricharan R <quic_srichara@xxxxxxxxxxx>
> + *	Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> + */
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/dmaengine.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/dma/qcom_adm.h>
> +#include <linux/dma/qcom_bam_dma.h>
> +#include <linux/module.h>
> +#include <linux/mtd/partitions.h>

Not sure why partitions.h is needed here?

> +#include <linux/mtd/rawnand.h>

No raw NAND include.

> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/mtd/nand-qpic-common.h>
> +#include <linux/mtd/spinand.h>

..

> +static int qcom_spi_ecc_init_ctx_pipelined(struct nand_device *nand)
> +{
> +	struct qcom_nand_controller *snandc = nand_to_qcom_snand(nand);
> +	struct nand_ecc_props *conf = &nand->ecc.ctx.conf;
> +	struct nand_ecc_props *reqs = &nand->ecc.requirements;
> +	struct nand_ecc_props *user = &nand->ecc.user_conf;
> +	struct mtd_info *mtd = nanddev_to_mtd(nand);
> +	int step_size = 0, strength = 0, steps;
> +	int cwperpage, bad_block_byte;
> +	struct qpic_ecc *ecc_cfg;
> +
> +	cwperpage = mtd->writesize / NANDC_STEP_SIZE;
> +	snandc->num_cw = cwperpage;
> +
> +	ecc_cfg = kzalloc(sizeof(*ecc_cfg), GFP_KERNEL);
> +	if (!ecc_cfg)
> +		return -ENOMEM;
> +
> +	nand->ecc.ctx.priv = ecc_cfg;
> +
> +	if (user->step_size && user->strength) {
> +		step_size = user->step_size;
> +		strength = user->strength;
> +	} else if (reqs->step_size && reqs->strength) {
> +		step_size = reqs->step_size;
> +		strength = reqs->strength;
> +	}
> +
> +	if (step_size && strength)
> +		steps = mtd->writesize / step_size;
> +
> +	ecc_cfg->ecc_bytes_hw = 7;
> +	ecc_cfg->spare_bytes = 4;
> +	ecc_cfg->bbm_size = 1;
> +	ecc_cfg->bch_enabled = true;
> +	ecc_cfg->bytes = ecc_cfg->ecc_bytes_hw + ecc_cfg->spare_bytes + ecc_cfg->bbm_size;
> +
> +	ecc_cfg->steps = 4;
> +	ecc_cfg->strength = 4;
> +	ecc_cfg->step_size = 512;
> +
> +	mtd_set_ooblayout(mtd, &qcom_spi_ooblayout);
> +
> +	ecc_cfg->cw_data = 516;
> +	ecc_cfg->cw_size = ecc_cfg->cw_data + ecc_cfg->bytes;
> +	bad_block_byte = mtd->writesize - ecc_cfg->cw_size * (cwperpage - 1) + 1;
> +
> +	ecc_cfg->cfg0 = (cwperpage - 1) << CW_PER_PAGE
> +				| ecc_cfg->cw_data << UD_SIZE_BYTES
> +				| 1 << DISABLE_STATUS_AFTER_WRITE
> +				| 3 << NUM_ADDR_CYCLES
> +				| ecc_cfg->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_RS
> +				| 0 << STATUS_BFR_READ
> +				| 1 << SET_RD_MODE_AFTER_STATUS
> +				| ecc_cfg->spare_bytes << SPARE_SIZE_BYTES;

Can we please use FIELD_GET/FIELD_SET?

Also I think the coding style proposes:

	val = foo |
	      bar;

instead of

	val = foo
	 	| bar;


..

> +static int qcom_spi_write_page_cache(struct qcom_nand_controller *snandc,
> +				     const struct spi_mem_op *op)
> +{
> +	struct qpic_snand_op s_op = {};
> +	u32 cmd;
> +
> +	cmd = qcom_spi_cmd_mapping(snandc, op->cmd.opcode);
> +	s_op.cmd_reg = cmd;
> +
> +	if (op->cmd.opcode == SPINAND_PROGRAM_LOAD) {
> +		if (snandc->page_rw)
> +			snandc->data_buf = (u8 *)op->data.buf.out;
> +		if (snandc->oob_rw)
> +			snandc->oob_buf = (u8 *)op->data.buf.out;

Quick comment: looks wrong, no?

> +	}
> +
> +	return 0;
> +}
> +
> +static int qcom_spi_send_cmdaddr(struct qcom_nand_controller *snandc,
> +				 const struct spi_mem_op *op)
> +{
> +	struct qpic_snand_op s_op = {};
> +	u32 cmd;
> +	int ret, opcode;
> +
> +	cmd = qcom_spi_cmd_mapping(snandc, op->cmd.opcode);
> +
> +	s_op.cmd_reg = cmd;
> +	s_op.addr1_reg = op->addr.val;
> +	s_op.addr2_reg = 0;
> +
> +	opcode = op->cmd.opcode;
> +
> +	switch (opcode) {
> +	case SPINAND_WRITE_EN:
> +		return 0;
> +	case SPINAND_PROGRAM_EXECUTE:
> +		s_op.addr1_reg = op->addr.val << 16;
> +		s_op.addr2_reg = op->addr.val >> 16 & 0xff;
> +		snandc->addr1 = s_op.addr1_reg;
> +		snandc->addr2 = s_op.addr2_reg;
> +		snandc->cmd = cmd;
> +		return qcom_spi_program_execute(snandc, op);
> +	case SPINAND_READ:
> +		s_op.addr1_reg = (op->addr.val << 16);
> +		s_op.addr2_reg = op->addr.val >> 16 & 0xff;
> +		snandc->addr1 = s_op.addr1_reg;
> +		snandc->addr2 = s_op.addr2_reg;
> +		snandc->cmd = cmd;
> +		return 0;
> +	case SPINAND_ERASE:
> +		s_op.addr2_reg = (op->addr.val >> 16) & 0xffff;
> +		s_op.addr1_reg = op->addr.val;
> +		snandc->addr1 = s_op.addr1_reg;
> +		snandc->addr1 <<= 16;

Feels wrong as well

> +		snandc->addr2 = s_op.addr2_reg;
> +		snandc->cmd = cmd;
> +		qcom_spi_block_erase(snandc);
> +		return 0;
> +	default:
> +		break;
> +	}
> +
> +	snandc->buf_count = 0;
> +	snandc->buf_start = 0;
> +	qcom_clear_read_regs(snandc);
> +	qcom_clear_bam_transaction(snandc);
> +
> +	snandc->regs->cmd = s_op.cmd_reg;
> +	snandc->regs->exec = 1;
> +	snandc->regs->addr0 = s_op.addr1_reg;
> +	snandc->regs->addr1 = s_op.addr2_reg;
> +
> +	qcom_write_reg_dma(snandc, &snandc->regs->cmd, NAND_FLASH_CMD, 3, NAND_BAM_NEXT_SGL);
> +	qcom_write_reg_dma(snandc, &snandc->regs->exec, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +
> +	ret = qcom_submit_descs(snandc);
> +	if (ret)
> +		dev_err(snandc->dev, "failure in sbumitting cmd descriptor\n");
> +
> +	return ret;
> +}
> +
> +static int qcom_spi_io_op(struct qcom_nand_controller *snandc, const struct spi_mem_op *op)
> +{
> +	int ret, val, opcode;
> +	bool copy = false, copy_ftr = false;
> +
> +	ret = qcom_spi_send_cmdaddr(snandc, op);
> +	if (ret)
> +		return ret;
> +
> +	snandc->buf_count = 0;
> +	snandc->buf_start = 0;
> +	qcom_clear_read_regs(snandc);
> +	qcom_clear_bam_transaction(snandc);
> +	opcode = op->cmd.opcode;
> +
> +	switch (opcode) {
> +	case SPINAND_READID:
> +		snandc->buf_count = 4;
> +		qcom_read_reg_dma(snandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
> +		copy = true;
> +		break;
> +	case SPINAND_GET_FEATURE:
> +		snandc->buf_count = 4;
> +		qcom_read_reg_dma(snandc, NAND_FLASH_FEATURES, 1, NAND_BAM_NEXT_SGL);
> +		copy_ftr = true;
> +		break;
> +	case SPINAND_SET_FEATURE:
> +		snandc->regs->flash_feature = *(u32 *)op->data.buf.out;
> +		qcom_write_reg_dma(snandc, &snandc->regs->flash_feature,
> +				   NAND_FLASH_FEATURES, 1, NAND_BAM_NEXT_SGL);
> +		break;
> +	default:
> +		return 0;

No error state?

> +	}
> +
> +	ret = qcom_submit_descs(snandc);
> +	if (ret)
> +		dev_err(snandc->dev, "failure in submitting descriptor for:%d\n", opcode);
> +
> +	if (copy) {
> +		qcom_nandc_dev_to_mem(snandc, true);
> +		memcpy(op->data.buf.in, snandc->reg_read_buf, snandc->buf_count);
> +	}
> +
> +	if (copy_ftr) {
> +		qcom_nandc_dev_to_mem(snandc, true);
> +		val = le32_to_cpu(*(__le32 *)snandc->reg_read_buf);
> +		val >>= 8;
> +		memcpy(op->data.buf.in, &val, snandc->buf_count);
> +	}
> +
> +	return ret;
> +}
> +
> +static bool qcom_spi_is_page_op(const struct spi_mem_op *op)
> +{
> +	if (op->addr.buswidth != 1 && op->addr.buswidth != 2 && op->addr.buswidth != 4)
> +		return false;
> +
> +	if (op->data.dir == SPI_MEM_DATA_IN) {
> +		if (op->addr.buswidth == 4 && op->data.buswidth == 4)
> +			return true;
> +
> +		if (op->addr.nbytes == 2 && op->addr.buswidth == 1)
> +			return true;
> +
> +	} else if (op->data.dir == SPI_MEM_DATA_OUT) {
> +		if (op->data.buswidth == 4)
> +			return true;
> +		if (op->addr.nbytes == 2 && op->addr.buswidth == 1)
> +			return true;
> +	}
> +
> +	return false;
> +}
> +
> +static bool qcom_spi_supports_op(struct spi_mem *mem, const struct spi_mem_op *op)
> +{
> +	if (!spi_mem_default_supports_op(mem, op))
> +		return false;
> +
> +	if (op->cmd.nbytes != 1 || op->cmd.buswidth != 1)
> +		return false;
> +
> +	if (qcom_spi_is_page_op(op))
> +		return true;
> +
> +	return ((!op->addr.nbytes || op->addr.buswidth == 1) &&
> +		(!op->dummy.nbytes || op->dummy.buswidth == 1) &&
> +		(!op->data.nbytes || op->data.buswidth == 1));
> +}
> +
> +static int qcom_spi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
> +{
> +	struct qcom_nand_controller *snandc = spi_controller_get_devdata(mem->spi->controller);
> +
> +	dev_dbg(snandc->dev, "OP %02x ADDR %08llX@%d:%u DATA %d:%u", op->cmd.opcode,
> +		op->addr.val, op->addr.buswidth, op->addr.nbytes,
> +		op->data.buswidth, op->data.nbytes);
> +
> +	if (qcom_spi_is_page_op(op)) {
> +		if (op->data.dir == SPI_MEM_DATA_IN)
> +			return qcom_spi_read_page_cache(snandc, op);
> +		if (op->data.dir == SPI_MEM_DATA_OUT)
> +			return qcom_spi_write_page_cache(snandc, op);
> +	} else {
> +		return qcom_spi_io_op(snandc, op);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct spi_controller_mem_ops qcom_spi_mem_ops = {
> +	.supports_op = qcom_spi_supports_op,
> +	.exec_op = qcom_spi_exec_op,
> +};
> +
> +static const struct spi_controller_mem_caps qcom_spi_mem_caps = {
> +	.ecc = true,
> +};
> +
> +static int qcom_spi_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct spi_controller *ctlr;
> +	struct qcom_nand_controller *snandc;
> +	struct resource *res;
> +	const void *dev_data;
> +	struct qpic_ecc *ecc;
> +	int ret;
> +
> +	ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL);
> +	if (!ecc)
> +		return -ENOMEM;
> +
> +	ctlr = __devm_spi_alloc_controller(dev, sizeof(*snandc), false);
> +	if (!ctlr)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, ctlr);
> +
> +	snandc = spi_controller_get_devdata(ctlr);
> +
> +	snandc->ctlr = ctlr;
> +	snandc->dev = dev;
> +	snandc->ecc = ecc;
> +
> +	snandc->oob_buf = devm_kzalloc(dev, OOB_BUF_SIZE, GFP_KERNEL);
> +	if (!snandc->oob_buf)
> +		return -ENOMEM;
> +
> +	dev_data = of_device_get_match_data(dev);
> +	if (!dev_data) {
> +		dev_err(&pdev->dev, "failed to get device data\n");
> +		return -ENODEV;
> +	}
> +
> +	snandc->props = dev_data;
> +	snandc->dev = &pdev->dev;
> +
> +	snandc->core_clk = devm_clk_get(dev, "core");
> +	if (IS_ERR(snandc->core_clk))
> +		return PTR_ERR(snandc->core_clk);
> +
> +	snandc->aon_clk = devm_clk_get(dev, "aon");
> +	if (IS_ERR(snandc->aon_clk))
> +		return PTR_ERR(snandc->aon_clk);
> +
> +	snandc->iomacro_clk = devm_clk_get(dev, "iom");
> +	if (IS_ERR(snandc->iomacro_clk))
> +		return PTR_ERR(snandc->iomacro_clk);
> +
> +	snandc->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
> +	if (IS_ERR(snandc->base))
> +		return PTR_ERR(snandc->base);
> +
> +	snandc->base_phys = res->start;
> +	snandc->base_dma = dma_map_resource(dev, res->start, resource_size(res),
> +					    DMA_BIDIRECTIONAL, 0);
> +	if (dma_mapping_error(dev, snandc->base_dma))
> +		return -ENXIO;
> +
> +	ret = clk_prepare_enable(snandc->core_clk);
> +	if (ret)
> +		goto err_core_clk;

error labels should point at the next freeing instruction, they should
not be named against where they are called.

Same below.

> +
> +	ret = clk_prepare_enable(snandc->aon_clk);
> +	if (ret)
> +		goto err_aon_clk;
> +
> +	ret = clk_prepare_enable(snandc->iomacro_clk);
> +	if (ret)
> +		goto err_snandc_alloc;

This label is really badly named

> +
> +	ret = qcom_nandc_alloc(snandc);
> +	if (ret)
> +		goto err_iom_clk;

		goto err_dis_iom_clk; ?

> +
> +	ret = qcom_spi_init(snandc);
> +	if (ret)
> +		goto err_init;
> +
> +	/* setup ECC engine */
> +	snandc->ecc_eng.dev = &pdev->dev;
> +	snandc->ecc_eng.integration = NAND_ECC_ENGINE_INTEGRATION_PIPELINED;
> +	snandc->ecc_eng.ops = &qcom_spi_ecc_engine_ops_pipelined;
> +	snandc->ecc_eng.priv = snandc;
> +
> +	ret = nand_ecc_register_on_host_hw_engine(&snandc->ecc_eng);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to register ecc engine.\n");

Maybe you can print the error if we want the dev_err() call to be
useful?

> +		goto err_init;
> +	}
> +
> +	ctlr->num_chipselect = QPIC_QSPI_NUM_CS;
> +	ctlr->mem_ops = &qcom_spi_mem_ops;
> +	ctlr->mem_caps = &qcom_spi_mem_caps;
> +	ctlr->dev.of_node = pdev->dev.of_node;
> +	ctlr->mode_bits = SPI_TX_DUAL | SPI_RX_DUAL |
> +			    SPI_TX_QUAD | SPI_RX_QUAD;
> +
> +	ret = spi_register_controller(ctlr);
> +	if (ret) {
> +		dev_err(&pdev->dev, "spi_register_controller failed.\n");
> +		goto err_init;
> +	}
> +
> +	return 0;
> +
> +err_init:
> +	qcom_nandc_unalloc(snandc);
> +err_iom_clk:
> +	clk_disable_unprepare(snandc->iomacro_clk);
> +err_snandc_alloc:
> +	clk_disable_unprepare(snandc->aon_clk);
> +err_aon_clk:
> +	clk_disable_unprepare(snandc->core_clk);
> +err_core_clk:
> +	dma_unmap_resource(dev, res->start, resource_size(res),
> +			   DMA_BIDIRECTIONAL, 0);
> +	return ret;
> +}
> +
> +static int qcom_spi_remove(struct platform_device *pdev)
> +{
> +	struct spi_controller *ctlr = platform_get_drvdata(pdev);
> +	struct qcom_nand_controller *snandc = spi_controller_get_devdata(ctlr);
> +	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +
> +	spi_unregister_controller(ctlr);
> +
> +	clk_disable_unprepare(snandc->aon_clk);
> +	clk_disable_unprepare(snandc->core_clk);
> +	clk_disable_unprepare(snandc->iomacro_clk);
> +
> +	dma_unmap_resource(&pdev->dev, snandc->base_dma, resource_size(res),
> +			   DMA_BIDIRECTIONAL, 0);

No unalloc?

BTW unalloc is a bit weird. "free" or "cleanup" might be better.

> +	return 0;
> +}
> +
> +static const struct qcom_nandc_props ipq9574_snandc_props = {
> +	.dev_cmd_reg_start = 0x7000,
> +	.supports_bam = true,
> +};
> +
> +static const struct of_device_id qcom_snandc_of_match[] = {
> +	{
> +		.compatible = "qcom,spi-qpic-snand",
> +		.data = &ipq9574_snandc_props,
> +	},
> +	{}
> +}
> +MODULE_DEVICE_TABLE(of, qcom_snandc_of_match);
> +
> +static struct platform_driver qcom_spi_driver = {
> +	.driver = {
> +		.name		= "qcom_snand",
> +		.of_match_table = qcom_snandc_of_match,
> +	},
> +	.probe = qcom_spi_probe,
> +	.remove = qcom_spi_remove,
> +};
> +module_platform_driver(qcom_spi_driver);
> +
> +MODULE_DESCRIPTION("SPI driver for QPIC QSPI cores");
> +MODULE_AUTHOR("Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mtd/nand-qpic-common.h b/include/linux/mtd/nand-qpic-common.h
> index 096c15d3be76..dd2b56125bc1 100644
> --- a/include/linux/mtd/nand-qpic-common.h
> +++ b/include/linux/mtd/nand-qpic-common.h
> @@ -315,11 +315,56 @@ struct nandc_regs {
>  	__le32 read_location_last1;
>  	__le32 read_location_last2;
>  	__le32 read_location_last3;
> +	__le32 spi_cfg;
> +	__le32 num_addr_cycle;
> +	__le32 busy_wait_cnt;
> +	__le32 flash_feature;
>  
>  	__le32 erased_cw_detect_cfg_clr;
>  	__le32 erased_cw_detect_cfg_set;
>  };
>  
> +/*
> + * ECC state struct
> + * @corrected:		ECC corrected
> + * @bitflips:		Max bit flip
> + * @failed:		ECC failed
> + */
> +struct qcom_ecc_stats {
> +	u32 corrected;
> +	u32 bitflips;
> +	u32 failed;
> +};
> +
> +struct qpic_ecc {
> +	struct device *dev;
> +	const struct qpic_ecc_caps *caps;
> +	struct completion done;
> +	u32 sectors;
> +	u8 *eccdata;
> +	bool use_ecc;
> +	u32 ecc_modes;
> +	int ecc_bytes_hw;
> +	int spare_bytes;
> +	int bbm_size;
> +	int ecc_mode;
> +	int bytes;
> +	int steps;
> +	int step_size;
> +	int strength;
> +	int cw_size;
> +	int cw_data;
> +	u32 cfg0, cfg1;
> +	u32 cfg0_raw, cfg1_raw;
> +	u32 ecc_buf_cfg;
> +	u32 ecc_bch_cfg;
> +	u32 clrflashstatus;
> +	u32 clrreadstatus;
> +	bool bch_enabled;
> +};
> +
> +struct qpic_ecc;
> +
>  /*
>   * NAND controller data struct
>   *
> @@ -329,6 +374,7 @@ struct nandc_regs {
>   *
>   * @core_clk:			controller clock
>   * @aon_clk:			another controller clock
> + * @iomacro_clk:		io macro clock
>   *
>   * @regs:			a contiguous chunk of memory for DMA register
>   *				writes. contains the register values to be
> @@ -338,6 +384,7 @@ struct nandc_regs {
>   *				initialized via DT match data
>   *
>   * @controller:			base controller structure
> + * @ctlr:			spi controller structure
>   * @host_list:			list containing all the chips attached to the
>   *				controller
>   *
> @@ -375,6 +422,7 @@ struct qcom_nand_controller {
>  
>  	struct clk *core_clk;
>  	struct clk *aon_clk;
> +	struct clk *iomacro_clk;
>  
>  	struct nandc_regs *regs;
>  	struct bam_transaction *bam_txn;
> @@ -382,6 +430,7 @@ struct qcom_nand_controller {
>  	const struct qcom_nandc_props *props;
>  
>  	struct nand_controller controller;
> +	struct spi_controller *ctlr;
>  	struct list_head host_list;
>  
>  	union {
> @@ -418,6 +467,21 @@ struct qcom_nand_controller {
>  
>  	u32 cmd1, vld;
>  	bool exec_opwrite;
> +	struct qpic_ecc *ecc;
> +	struct qcom_ecc_stats ecc_stats;
> +	struct nand_ecc_engine ecc_eng;
> +	u8 *data_buf;
> +	u8 *oob_buf;
> +	u32 wlen;
> +	u32 addr1;
> +	u32 addr2;
> +	u32 cmd;
> +	u32 num_cw;
> +	u32 pagesize;
> +	bool oob_rw;
> +	bool page_rw;
> +	bool raw_rw;
> +	bool read_last_cw;
>  };

If all these definitions are only used by the spi controller, I don't
see why you want to put them in the common file.

Thanks,
Miquèl