Re: [PATCH v7 3/3] thunderbolt: To extend ASMedia NVM formats.

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Mon, Aug 29, 2022 at 07:10:59PM +0800, Szuying Chen wrote:
> From: Szuying Chen <Chloe_Chen@asmedia.com.tw>
> 
> The patch add ASMedia NVM formats. And add tb_switch_nvm_upgradeable()
> to enable firmware upgrade.
> 
> Signed-off-by: Szuying Chen <Chloe_Chen@asmedia.com.tw>
> ---
> Add ASMedia NVM formats. And fix asmedia_nvm_version() part of code so
> that easier to read.
> 
>  drivers/thunderbolt/nvm.c    | 68 ++++++++++++++++++++++++++++++++++++
>  drivers/thunderbolt/switch.c |  3 ++
>  drivers/thunderbolt/tb.h     |  1 +
>  3 files changed, 72 insertions(+)
> 
> diff --git a/drivers/thunderbolt/nvm.c b/drivers/thunderbolt/nvm.c
> index 91c8848b4d2e..c69db5b65f7d 100644
> --- a/drivers/thunderbolt/nvm.c
> +++ b/drivers/thunderbolt/nvm.c
> @@ -15,16 +15,25 @@
>  /* Switch NVM support */
>  #define NVM_CSS		0x10
> 
> +/* Vendor ID of the Router. It's assigned by the USB-IF */

Pretty useless comment.

> +#define ROUTER_VENDOR_ID_ASMEDIA 0x174c
> +
> +/* ASMedia specific NVM offsets */
> +#define ASMEDIA_NVM_DATE	0x1c
> +#define ASMEDIA_NVM_VERSION	0x28
> +
>  static DEFINE_IDA(nvm_ida);
> 
>  /**
>   * struct tb_nvm_vendor_ops - Vendor NVM specific operations
>   * @read_version: Used NVM read get Firmware version.
>   * @validate: Vendors have their validate method before NVM write.
> + * @nvm_upgrade: Enable NVM upgrade.
>   */
>  struct tb_nvm_vendor_ops {
>  	int (*read_version)(struct tb_switch *sw);
>  	int (*validate)(struct tb_switch *sw);
> +	void (*nvm_upgrade)(struct tb_switch *sw);
>  };
> 
>  static inline int nvm_read(struct tb_switch *sw, unsigned int address,
> @@ -128,11 +137,49 @@ static int intel_nvm_validate(struct tb_switch *sw)
>  	return 0;
>  }
> 
> +static int asmedia_nvm_version(struct tb_switch *sw)
> +{
> +	struct tb_nvm *nvm = sw->nvm;
> +	u32 val;
> +	int ret;
> +
> +	/* ASMedia get version and date format is xxxxxx.xxxxxx */
> +	ret = nvm_read(sw, ASMEDIA_NVM_VERSION, &val, sizeof(val));
> +	if (ret)
> +		return ret;
> +
> +	nvm->major = (((u8)val) << 0x10 | ((u8)(val >> 0x8)) << 0x8 | (u8)(val >> 0x10));
> +
> +	ret = nvm_read(sw, ASMEDIA_NVM_DATE, &val, sizeof(val));
> +	if (ret)
> +		return ret;
> +
> +	nvm->minor = (((u8)val) << 0x10 | ((u8)(val >> 0x8)) << 0x8 | (u8)(val >> 0x10));
> +
> +	/*
> +	 * Asmedia NVM size fixed on 512K. We currently have no plan
> +	 * to increase size in the future.
> +	 */
> +	nvm->nvm_size = SZ_512K;
> +
> +	return 0;
> +}
> +
> +static void tb_switch_set_nvm_upgrade(struct tb_switch *sw)
> +{
> +	sw->no_nvm_upgrade = false;
> +}
> +
>  static const struct tb_nvm_vendor_ops intel_switch_nvm_ops = {
>  	.read_version = intel_nvm_version,
>  	.validate = intel_nvm_validate,
>  };
> 
> +static const struct tb_nvm_vendor_ops asmedia_switch_nvm_ops = {
> +	.nvm_upgrade = tb_switch_set_nvm_upgrade,

This is bad name IMHO. It does not really upragade the NVM so perhaps
something like .nvm_upgradeable?

Hower, I don't think this is needed at all because instead of the hack
in tb_start():

	tb->root_switch->no_nvm_upgrade = true;

we should make this:

	tb->root_switch->no_nvm_upgrade = !tb_switch_is_usb4(sw);

and then it only depends on the fact whether the router implements the
necessary NVM operations (please double check if this actually works).

> +	.read_version = asmedia_nvm_version,
> +};
> +
>  struct switch_nvm_vendor {
>  	u16 vendor;
>  	const struct tb_nvm_vendor_ops *vops;
> @@ -143,6 +190,27 @@ static const struct switch_nvm_vendor switch_nvm_vendors[] = {
>  	{ 0x8087, &intel_switch_nvm_ops },
>  };
> 
> +/**
> + * tb_switch_nvm_upgradeable() - Enable NVM upgrade of a switch
> + * @sw: Switch whose NVM upgrade to enable
> + *
> + * This function must be called before creating the switch devices, it will
> + * make the no_active NVM device visible.

non_active

> + */
> +void tb_switch_nvm_upgradeable(struct tb_switch *sw)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(switch_nvm_vendors); i++) {
> +		const struct switch_nvm_vendor *v = &switch_nvm_vendors[i];
> +
> +		if (v->vendor == sw->config.vendor_id) {
> +			if (v->vops->nvm_upgrade)
> +				v->vops->nvm_upgrade(sw);
> +		}
> +	}
> +}
> +
>  /**
>   * tb_switch_nvm_validate() - Validate NVM image
>   * @switch: Switch to NVM write
> diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
> index 2dbfd75202bf..f8dc18f6c5c8 100644
> --- a/drivers/thunderbolt/switch.c
> +++ b/drivers/thunderbolt/switch.c
> @@ -2822,6 +2822,9 @@ int tb_switch_add(struct tb_switch *sw)
>  			return ret;
>  	}
> 
> +	/* Enable the NVM firmware upgrade */
> +	tb_switch_nvm_upgradeable(sw);
> +
>  	ret = device_add(&sw->dev);
>  	if (ret) {
>  		dev_err(&sw->dev, "failed to add device: %d\n", ret);
> diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
> index 9cf62d5f25d2..642af7473851 100644
> --- a/drivers/thunderbolt/tb.h
> +++ b/drivers/thunderbolt/tb.h
> @@ -773,6 +773,7 @@ int tb_switch_reset(struct tb_switch *sw);
>  int tb_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit,
>  			   u32 value, int timeout_msec);
>  int tb_switch_nvm_validate(struct tb_switch *sw);
> +void tb_switch_nvm_upgradeable(struct tb_switch *sw);
>  void tb_sw_set_unplugged(struct tb_switch *sw);
>  struct tb_port *tb_switch_find_port(struct tb_switch *sw,
> 				    enum tb_port_type type);
> --
> 2.34.1