diff mbox series

[v2,11/29] net/ena/base: use 48-bit memory addresses in ena_com

Message ID 20200401142127.13715-12-mk@semihalf.com (mailing list archive)
State Superseded, archived
Delegated to: Ferruh Yigit
Headers
Series Update ENA driver to v2.1.0 |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Michal Krawczyk April 1, 2020, 2:21 p.m. UTC 
  ENA device is using 48-bit memory for IO. because of that, the upper
limit had to be updated.

Signed-off-by: Michal Krawczyk <mk@semihalf.com>
Reviewed-by: Igor Chauskin <igorch@amazon.com>
Reviewed-by: Guy Tzalik <gtzalik@amazon.com>
---
 drivers/net/ena/base/ena_com.c                  | 2 +-
 drivers/net/ena/base/ena_defs/ena_common_defs.h | 6 +++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

Comments

Ferruh Yigit April 2, 2020, 12:55 p.m. UTC | #1 
On 4/1/2020 3:21 PM, Michal Krawczyk wrote:
> ENA device is using 48-bit memory for IO. because of that, the upper
> limit had to be updated.

What is the impact of this change, and what is the reason of the change? Can you
please explain in the commit log?

> 
> Signed-off-by: Michal Krawczyk <mk@semihalf.com>
> Reviewed-by: Igor Chauskin <igorch@amazon.com>
> Reviewed-by: Guy Tzalik <gtzalik@amazon.com>
> ---
>  drivers/net/ena/base/ena_com.c                  | 2 +-
>  drivers/net/ena/base/ena_defs/ena_common_defs.h | 6 +++++-
>  2 files changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ena/base/ena_com.c b/drivers/net/ena/base/ena_com.c
> index 7c1d0aef20..b7749209b3 100644
> --- a/drivers/net/ena/base/ena_com.c
> +++ b/drivers/net/ena/base/ena_com.c
> @@ -73,7 +73,7 @@ static int ena_com_mem_addr_set(struct ena_com_dev *ena_dev,
>  	}
>  
>  	ena_addr->mem_addr_low = lower_32_bits(addr);
> -	ena_addr->mem_addr_high = upper_32_bits(addr);
> +	ena_addr->mem_addr_high = (u16)upper_32_bits(addr);
>  
>  	return 0;
>  }
> diff --git a/drivers/net/ena/base/ena_defs/ena_common_defs.h b/drivers/net/ena/base/ena_defs/ena_common_defs.h
> index 1818c29a87..349474d265 100644
> --- a/drivers/net/ena/base/ena_defs/ena_common_defs.h
> +++ b/drivers/net/ena/base/ena_defs/ena_common_defs.h
> @@ -9,10 +9,14 @@
>  #define ENA_COMMON_SPEC_VERSION_MAJOR        2
>  #define ENA_COMMON_SPEC_VERSION_MINOR        0
>  
> +/* ENA operates with 48-bit memory addresses. ena_mem_addr_t */
>  struct ena_common_mem_addr {
>  	uint32_t mem_addr_low;
>  
> -	uint32_t mem_addr_high;
> +	uint16_t mem_addr_high;
> +
> +	/* MBZ */
> +	uint16_t reserved16;
>  };
>  
>  #endif /* _ENA_COMMON_H_ */
>
Michal Krawczyk April 3, 2020, 12:14 p.m. UTC | #2 
czw., 2 kwi 2020 o 14:55 Ferruh Yigit <ferruh.yigit@intel.com> napisał(a):
>
> On 4/1/2020 3:21 PM, Michal Krawczyk wrote:
> > ENA device is using 48-bit memory for IO. because of that, the upper
> > limit had to be updated.
>
> What is the impact of this change, and what is the reason of the change? Can you
> please explain in the commit log?
>

It's just a cosmetic change in our case and to align it with what the
device is in fact doing. Structure 'ena_common_mem_addr' could be
misleading - it was defining 64 bits for address, while the device in
fact could read up to 48 bits.

This value (address) is being verified before being set in
'ena_com_mem_addr_set()' function, so the functionality remains still
the same.

I'll update the commit log in v3.
diff mbox series

Patch

diff --git a/drivers/net/ena/base/ena_com.c b/drivers/net/ena/base/ena_com.c
index 7c1d0aef20..b7749209b3 100644
--- a/drivers/net/ena/base/ena_com.c
+++ b/drivers/net/ena/base/ena_com.c
@@ -73,7 +73,7 @@  static int ena_com_mem_addr_set(struct ena_com_dev *ena_dev,
 	}
 
 	ena_addr->mem_addr_low = lower_32_bits(addr);
-	ena_addr->mem_addr_high = upper_32_bits(addr);
+	ena_addr->mem_addr_high = (u16)upper_32_bits(addr);
 
 	return 0;
 }
diff --git a/drivers/net/ena/base/ena_defs/ena_common_defs.h b/drivers/net/ena/base/ena_defs/ena_common_defs.h
index 1818c29a87..349474d265 100644
--- a/drivers/net/ena/base/ena_defs/ena_common_defs.h
+++ b/drivers/net/ena/base/ena_defs/ena_common_defs.h
@@ -9,10 +9,14 @@ 
 #define ENA_COMMON_SPEC_VERSION_MAJOR        2
 #define ENA_COMMON_SPEC_VERSION_MINOR        0
 
+/* ENA operates with 48-bit memory addresses. ena_mem_addr_t */
 struct ena_common_mem_addr {
 	uint32_t mem_addr_low;
 
-	uint32_t mem_addr_high;
+	uint16_t mem_addr_high;
+
+	/* MBZ */
+	uint16_t reserved16;
 };
 
 #endif /* _ENA_COMMON_H_ */