Re: [tpmdd-devel] [PATCH v2 0/3] tpm_tis: Clean up force module parameter

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

On Thu, Dec 03, 2015 at 11:19:32AM -0700, Jason Gunthorpe wrote:
> On Thu, Dec 03, 2015 at 08:00:42AM +0200, Jarkko Sakkinen wrote:
> 
> > I guess it'd be more realiable. In my NUC the current fix works and the
> > people who tested it. If you supply me a fix that changes it to use that
> > I can test it and this will give also coverage to the people who tested
> > my original fix.
> 
> Here is the updated series:
> 
> https://github.com/jgunthorpe/linux/commits/for-jarkko
> 
> What does your dmesg say?
> 
> It really isn't OK to hardwire an address for acpi devices, so I've
> added something like this. Just completely guessing that control_pa is
> where the BIOS is hiding the base address. Maybe it is cca->cmd_pa ?

I'm a bit confused about the discussion because Martin replied that
tpm_tis used to get the address range before applying this series.

And pnp_driver in the backend for TPM 1.x devices grabs the address
range from DSDT.

/Jarkko

> From c9f7c0465008657f7fc7880496f68f4a1b3b4a26 Mon Sep 17 00:00:00 2001
> From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> Date: Thu, 3 Dec 2015 10:58:56 -0700
> Subject: [PATCH 3/5] tpm_tis: Do not fall back to a hardcoded address for TPM2
> 
> If the ACPI tables do not declare a memory resource for the TPM2
> then do not just fall back to the x86 default base address.
> 
> WIP: Guess that the control_address is the base address for the
> TIS 1.2 memory mapped interface.
> 
> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> ---
>  drivers/char/tpm/tpm_tis.c | 50 +++++++++++++++++++---------------------------
>  1 file changed, 20 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
> index fecd27b45fd1..6b28f8003425 100644
> --- a/drivers/char/tpm/tpm_tis.c
> +++ b/drivers/char/tpm/tpm_tis.c
> @@ -122,39 +122,11 @@ static inline int is_itpm(struct acpi_device *dev)
>  {
>  	return has_hid(dev, "INTC0102");
>  }
> -
> -static inline int is_fifo(struct acpi_device *dev)
> -{
> -	struct acpi_table_tpm2 *tbl;
> -	acpi_status st;
> -
> -	/* TPM 1.2 FIFO */
> -	if (!has_hid(dev, "MSFT0101"))
> -		return 1;
> -
> -	st = acpi_get_table(ACPI_SIG_TPM2, 1,
> -			    (struct acpi_table_header **) &tbl);
> -	if (ACPI_FAILURE(st)) {
> -		dev_err(&dev->dev, "failed to get TPM2 ACPI table\n");
> -		return 0;
> -	}
> -
> -	if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
> -		return 0;
> -
> -	/* TPM 2.0 FIFO */
> -	return 1;
> -}
>  #else
>  static inline int is_itpm(struct acpi_device *dev)
>  {
>  	return 0;
>  }
> -
> -static inline int is_fifo(struct acpi_device *dev)
> -{
> -	return 1;
> -}
>  #endif
>  
>  /* Before we attempt to access the TPM we must see that the valid bit is set.
> @@ -980,11 +952,21 @@ static int tpm_check_resource(struct acpi_resource *ares, void *data)
>  
>  static int tpm_tis_acpi_init(struct acpi_device *acpi_dev)
>  {
> +	struct acpi_table_tpm2 *tbl;
> +	acpi_status st;
>  	struct list_head resources;
> -	struct tpm_info tpm_info = tis_default_info;
> +	struct tpm_info tpm_info = {};
>  	int ret;
>  
> -	if (!is_fifo(acpi_dev))
> +	st = acpi_get_table(ACPI_SIG_TPM2, 1,
> +			    (struct acpi_table_header **) &tbl);
> +	if (ACPI_FAILURE(st)) {
> +		dev_err(&acpi_dev->dev,
> +			FW_BUG "failed to get TPM2 ACPI table\n");
> +		return -ENODEV;
> +	}
> +
> +	if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
>  		return -ENODEV;
>  
>  	INIT_LIST_HEAD(&resources);
> @@ -996,6 +978,14 @@ static int tpm_tis_acpi_init(struct acpi_device *acpi_dev)
>  
>  	acpi_dev_free_resource_list(&resources);
>  
> +	if (tpm_info.start == 0 && tpm_info.len == 0) {
> +		tpm_info.start = tbl->control_address;
> +		tpm_info.len = TIS_MEM_LEN;
> +		dev_err(&acpi_dev->dev,
> +			FW_BUG "TPM2 ACPI table does not define a memory resource, using 0x%lx instead\n",
> +			tpm_info.start);
> +	}
> +
>  	if (is_itpm(acpi_dev))
>  		itpm = true;
>  
> -- 
> 2.1.4
>