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

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

On 3/19/2024 6:39 PM, Miquel Raynal wrote:
> Hi,
> 
> quic_mdalam@quicinc.com wrote on Tue, 19 Mar 2024 17:46:05 +0530:
> 
>> 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.
> 
> Maybe we should not expose qcom_nand_controller at all and just share
> the minimum bits which are really common.

  Will move all the header files to .c file from nand-qpic-common.h

> 
> Thanks,
> Miquèl

Thanks,
Alam.