Re: [PATCH v4 35/35] mtd: rawnand: allocate dynamically ONFI parameters during detection

[Boris Brezillon <boris.brezillon@bootlin.com>]

On Fri, 20 Jul 2018 17:15:27 +0200
Miquel Raynal <miquel.raynal@bootlin.com> wrote:

> Now that it is possible to do dynamic allocations during the
> identification phase, convert the onfi_params structure (which is only
> needed with ONFI compliant chips) into a pointer that will be allocated
> only if needed.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  drivers/mtd/nand/raw/nand_base.c    | 54 +++++++++++++++++++++++--------------
>  drivers/mtd/nand/raw/nand_micron.c  |  6 ++---
>  drivers/mtd/nand/raw/nand_timings.c | 12 ++++-----
>  include/linux/mtd/rawnand.h         |  6 ++---
>  4 files changed, 46 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> index 8645f655e5b0..ed9e2f1578e6 100644
> --- a/drivers/mtd/nand/raw/nand_base.c
> +++ b/drivers/mtd/nand/raw/nand_base.c
> @@ -5151,6 +5151,8 @@ static int nand_flash_detect_onfi(struct nand_chip *chip)
>  {
>  	struct mtd_info *mtd = nand_to_mtd(chip);
>  	struct nand_onfi_params *p;
> +	struct onfi_params *onfi;
> +	int onfi_version = 0;
>  	char id[4];
>  	int i, ret, val;
>  
> @@ -5206,21 +5208,19 @@ static int nand_flash_detect_onfi(struct nand_chip *chip)
>  	/* Check version */
>  	val = le16_to_cpu(p->revision);
>  	if (val & ONFI_VERSION_2_3)
> -		chip->parameters.onfi.version = 23;
> +		onfi_version = 23;
>  	else if (val & ONFI_VERSION_2_2)
> -		chip->parameters.onfi.version = 22;
> +		onfi_version = 22;
>  	else if (val & ONFI_VERSION_2_1)
> -		chip->parameters.onfi.version = 21;
> +		onfi_version = 21;
>  	else if (val & ONFI_VERSION_2_0)
> -		chip->parameters.onfi.version = 20;
> +		onfi_version = 20;
>  	else if (val & ONFI_VERSION_1_0)
> -		chip->parameters.onfi.version = 10;
> +		onfi_version = 10;
>  
> -	if (!chip->parameters.onfi.version) {
> +	if (!onfi_version) {
>  		pr_info("unsupported ONFI version: %d\n", val);
>  		goto free_onfi_param_page;
> -	} else {
> -		ret = 1;
>  	}
>  
>  	sanitize_string(p->manufacturer, sizeof(p->manufacturer));
> @@ -5257,7 +5257,7 @@ static int nand_flash_detect_onfi(struct nand_chip *chip)
>  	if (p->ecc_bits != 0xff) {
>  		chip->ecc_strength_ds = p->ecc_bits;
>  		chip->ecc_step_ds = 512;
> -	} else if (chip->parameters.onfi.version >= 21 &&
> +	} else if (onfi_version >= 21 &&
>  		(le16_to_cpu(p->features) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
>  
>  		/*
> @@ -5284,19 +5284,33 @@ static int nand_flash_detect_onfi(struct nand_chip *chip)
>  		bitmap_set(chip->parameters.set_feature_list,
>  			   ONFI_FEATURE_ADDR_TIMING_MODE, 1);
>  	}
> -	chip->parameters.onfi.tPROG = le16_to_cpu(p->t_prog);
> -	chip->parameters.onfi.tBERS = le16_to_cpu(p->t_bers);
> -	chip->parameters.onfi.tR = le16_to_cpu(p->t_r);
> -	chip->parameters.onfi.tCCS = le16_to_cpu(p->t_ccs);
> -	chip->parameters.onfi.async_timing_mode =
> -		le16_to_cpu(p->async_timing_mode);
> -	chip->parameters.onfi.vendor_revision =
> -		le16_to_cpu(p->vendor_revision);
> -	memcpy(chip->parameters.onfi.vendor, p->vendor,
> -	       sizeof(p->vendor));
>  
> +	onfi = kzalloc(sizeof(*onfi), GFP_KERNEL);
> +	if (!onfi) {
> +		ret = -ENOMEM;
> +		goto free_model;
> +	}
> +
> +	onfi->version = onfi_version;
> +	onfi->tPROG = le16_to_cpu(p->t_prog);
> +	onfi->tBERS = le16_to_cpu(p->t_bers);
> +	onfi->tR = le16_to_cpu(p->t_r);
> +	onfi->tCCS = le16_to_cpu(p->t_ccs);
> +	onfi->async_timing_mode = le16_to_cpu(p->async_timing_mode);
> +	onfi->vendor_revision = le16_to_cpu(p->vendor_revision);
> +	memcpy(onfi->vendor, p->vendor, sizeof(p->vendor));
> +	chip->parameters.onfi = onfi;
> +
> +	/* Identification done, free the full ONFI parameter page and exit */
> +	kfree(p);
> +
> +	return 1;
> +
> +free_model:
> +	kfree(chip->parameters.model);
>  free_onfi_param_page:
>  	kfree(p);
> +
>  	return ret;
>  }
>  
> @@ -5693,7 +5707,6 @@ static int nand_detect(struct nand_chip *chip, struct nand_flash_dev *type)
>  		}
>  	}
>  
> -	chip->parameters.onfi.version = 0;
>  	if (!type->name || !type->pagesize) {
>  		/* Check if the chip is ONFI compliant */
>  		ret = nand_flash_detect_onfi(chip);
> @@ -6039,6 +6052,7 @@ static int nand_scan_ident(struct mtd_info *mtd, int maxchips,
>  static void nand_scan_ident_cleanup(struct nand_chip *chip)
>  {
>  	kfree(chip->parameters.model);
> +	kfree(chip->parameters.onfi);
>  }
>  
>  static int nand_set_ecc_soft_ops(struct mtd_info *mtd)
> diff --git a/drivers/mtd/nand/raw/nand_micron.c b/drivers/mtd/nand/raw/nand_micron.c
> index 656947d91841..8466a1740b3b 100644
> --- a/drivers/mtd/nand/raw/nand_micron.c
> +++ b/drivers/mtd/nand/raw/nand_micron.c
> @@ -88,9 +88,9 @@ static int micron_nand_setup_read_retry(struct mtd_info *mtd, int retry_mode)
>  static int micron_nand_onfi_init(struct nand_chip *chip)
>  {
>  	struct nand_parameters *p = &chip->parameters;
> -	struct nand_onfi_vendor_micron *micron = (void *)p->onfi.vendor;
> +	struct nand_onfi_vendor_micron *micron = (void *)p->onfi->vendor;
>  
> -	if (chip->parameters.onfi.version && p->onfi.vendor_revision) {
> +	if (p->onfi && p->onfi->vendor_revision) {

I think p->onfi != NULL guarantees that p->onfi->vendor_revision != 0.
if (p->onfi) should be enough.

Looks good otherwise.

Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>

>  		chip->read_retries = micron->read_retry_options;
>  		chip->setup_read_retry = micron_nand_setup_read_retry;
>  	}
> @@ -382,7 +382,7 @@ static int micron_supports_on_die_ecc(struct nand_chip *chip)
>  	u8 id[5];
>  	int ret;
>  
> -	if (!chip->parameters.onfi.version)
> +	if (!chip->parameters.onfi)
>  		return MICRON_ON_DIE_UNSUPPORTED;
>  
>  	if (chip->bits_per_cell != 1)
> diff --git a/drivers/mtd/nand/raw/nand_timings.c b/drivers/mtd/nand/raw/nand_timings.c
> index 9bb599106a31..ebc7b5f76f77 100644
> --- a/drivers/mtd/nand/raw/nand_timings.c
> +++ b/drivers/mtd/nand/raw/nand_timings.c
> @@ -294,6 +294,7 @@ int onfi_fill_data_interface(struct nand_chip *chip,
>  			     int timing_mode)
>  {
>  	struct nand_data_interface *iface = &chip->data_interface;
> +	struct onfi_params *onfi = chip->parameters.onfi;
>  
>  	if (type != NAND_SDR_IFACE)
>  		return -EINVAL;
> @@ -308,17 +309,16 @@ int onfi_fill_data_interface(struct nand_chip *chip,
>  	 * tPROG, tBERS, tR and tCCS.
>  	 * These information are part of the ONFI parameter page.
>  	 */
> -	if (chip->parameters.onfi.version) {
> -		struct nand_parameters *params = &chip->parameters;
> +	if (onfi) {
>  		struct nand_sdr_timings *timings = &iface->timings.sdr;
>  
>  		/* microseconds -> picoseconds */
> -		timings->tPROG_max = 1000000ULL * params->onfi.tPROG;
> -		timings->tBERS_max = 1000000ULL * params->onfi.tBERS;
> -		timings->tR_max = 1000000ULL * params->onfi.tR;
> +		timings->tPROG_max = 1000000ULL * onfi->tPROG;
> +		timings->tBERS_max = 1000000ULL * onfi->tBERS;
> +		timings->tR_max = 1000000ULL * onfi->tR;
>  
>  		/* nanoseconds -> picoseconds */
> -		timings->tCCS_min = 1000UL * params->onfi.tCCS;
> +		timings->tCCS_min = 1000UL * onfi->tCCS;
>  	} else {
>  		struct nand_sdr_timings *timings = &iface->timings.sdr;
>  		/*
> diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h
> index 5723d940a47d..8074cbd4e3fe 100644
> --- a/include/linux/mtd/rawnand.h
> +++ b/include/linux/mtd/rawnand.h
> @@ -488,7 +488,7 @@ struct nand_parameters {
>  	DECLARE_BITMAP(get_feature_list, ONFI_FEATURE_NUMBER);
>  
>  	/* ONFI parameters */
> -	struct onfi_params onfi;
> +	struct onfi_params *onfi;
>  };
>  
>  /* The maximum expected count of bytes in the NAND ID sequence */
> @@ -1618,10 +1618,10 @@ struct platform_nand_data {
>  /* return the supported asynchronous timing mode. */
>  static inline int onfi_get_async_timing_mode(struct nand_chip *chip)
>  {
> -	if (!chip->parameters.onfi.version)
> +	if (!chip->parameters.onfi)
>  		return ONFI_TIMING_MODE_UNKNOWN;
>  
> -	return chip->parameters.onfi.async_timing_mode;
> +	return chip->parameters.onfi->async_timing_mode;
>  }
>  
>  int onfi_fill_data_interface(struct nand_chip *chip,