Re: [PATCH v4 2/5] drivers: mtd: nand: Add qpic_common API file

[Md Sadre Alam <quic_mdalam@quicinc.com>]

On 3/19/2024 4:13 PM, Miquel Raynal wrote:
> Hi,
> 
>>>> +/**
>>>> + * qcom_offset_to_nandc_reg() - Get the actual offset
>>>> + * @regs: pointer to nandc_reg structure
>>>> + * @offset: register offset
>>>> + *
>>>> + * This function will reurn the actual offset for qpic controller register
>>>> + */
>>>> +__le32 *qcom_offset_to_nandc_reg(struct nandc_regs *regs, int offset)
>>>> +{
>>>> +	switch (offset) {
>>>> +	case NAND_FLASH_CMD:
>>>> +		return &regs->cmd;
>>>> +	case NAND_ADDR0:
>>>> +		return &regs->addr0;
>>>> +	case NAND_ADDR1:
>>>> +		return &regs->addr1;
>>>> +	case NAND_FLASH_CHIP_SELECT:
>>>> +		return &regs->chip_sel;
>>>> +	case NAND_EXEC_CMD:
>>>> +		return &regs->exec;
>>>> +	case NAND_FLASH_STATUS:
>>>> +		return &regs->clrflashstatus;
>>>> +	case NAND_DEV0_CFG0:
>>>> +		return &regs->cfg0;
>>>> +	case NAND_DEV0_CFG1:
>>>> +		return &regs->cfg1;
>>>> +	case NAND_DEV0_ECC_CFG:
>>>> +		return &regs->ecc_bch_cfg;
>>>> +	case NAND_READ_STATUS:
>>>> +		return &regs->clrreadstatus;
>>>> +	case NAND_DEV_CMD1:
>>>> +		return &regs->cmd1;
>>>> +	case NAND_DEV_CMD1_RESTORE:
>>>> +		return &regs->orig_cmd1;
>>>> +	case NAND_DEV_CMD_VLD:
>>>> +		return &regs->vld;
>>>> +	case NAND_DEV_CMD_VLD_RESTORE:
>>>> +		return &regs->orig_vld;
>>>> +	case NAND_EBI2_ECC_BUF_CFG:
>>>> +		return &regs->ecc_buf_cfg;
>>>> +	case NAND_READ_LOCATION_0:
>>>> +		return &regs->read_location0;
>>>> +	case NAND_READ_LOCATION_1:
>>>> +		return &regs->read_location1;
>>>> +	case NAND_READ_LOCATION_2:
>>>> +		return &regs->read_location2;
>>>> +	case NAND_READ_LOCATION_3:
>>>> +		return &regs->read_location3;
>>>> +	case NAND_READ_LOCATION_LAST_CW_0:
>>>> +		return &regs->read_location_last0;
>>>> +	case NAND_READ_LOCATION_LAST_CW_1:
>>>> +		return &regs->read_location_last1;
>>>> +	case NAND_READ_LOCATION_LAST_CW_2:
>>>> +		return &regs->read_location_last2;
>>>> +	case NAND_READ_LOCATION_LAST_CW_3:
>>>> +		return &regs->read_location_last3;
>>>
>>> Why do you need this indirection?
>>
>> This indirection I believe is needed by the write_reg_dma function,
>> wherein a bunch of registers are modified based on a starting register.
>> Can I change this in a separate cleanup series as a follow up to this?
> 
> I think it would be cleaner to make the changes I requested first and
> then make a copy. I understand it is more work on your side, so if you
> really prefer you can (1) make the copy and then (2) clean it all. But
> please do it all in this series.
Ok
> 
>>>> diff --git a/include/linux/mtd/nand-qpic-common.h b/include/linux/mtd/nand-qpic-common.h
>>>> new file mode 100644
>>>> index 000000000000..aced15866627
>>>> --- /dev/null
>>>> +++ b/include/linux/mtd/nand-qpic-common.h
>>>> @@ -0,0 +1,486 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/*
>>>> + * QCOM QPIC common APIs header file
>>>> + *
>>>> + * Copyright (c) 2023 Qualcomm Inc.
>>>> + * Authors:     Md sadre Alam           <quic_mdalam@quicinc.com>
>>>> + *		Sricharan R             <quic_srichara@quicinc.com>
>>>> + *		Varadarajan Narayanan   <quic_varada@quicinc.com>
>>>> + *
>>>> + */
>>>> +#ifndef __MTD_NAND_QPIC_COMMON_H__
>>>> +#define __MTD_NAND_QPIC_COMMON_H__
>>>> +
>>>> +#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>
>>>> +#include <linux/mtd/rawnand.h>
>>>
>>> You really need this?
>> Yes , since some generic structure used here.
> 
> Which ones? If this is a common file, you probably should not.
  Since we are using this struct qcom_nand_controller { }
  for both SPI nand as well as raw nand. In this we are having this
  struct nand_controller controller member.
> 
> Thanks,
> Miquèl

Thanks,
Alam.