diff mbox series

[iwl-next,v1,01/13] e1000e: make lost bits explicit

Message ID 20231121211921.19834-2-jesse.brandeburg@intel.com (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series intel: use FIELD_PREP and FIELD_GET | expand

Checks

Context Check Description
netdev/tree_selection success Guessing tree name failed - patch did not apply, async

Commit Message

Jesse Brandeburg Nov. 21, 2023, 9:19 p.m. UTC 
For more than 15 years this code has passed in a request for a page and
masked off that page when read/writing. This code has been here forever,
but FIELD_PREP finds the bug when converted to use it. Change the code
to do exactly the same thing but allow the conversion to FIELD_PREP in a
later patch. To make it clear what we lost when making this change I
left a comment, but there is no point to change the code to generate a
correct sequence at this point.

This is not a Fixes tagged patch on purpose because it doesn't change
the binary output.

Reviewed-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
---
 drivers/net/ethernet/intel/e1000e/80003es2lan.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

Comments

Simon Horman Nov. 24, 2023, 10:59 a.m. UTC | #1 
On Tue, Nov 21, 2023 at 01:19:09PM -0800, Jesse Brandeburg wrote:
> For more than 15 years this code has passed in a request for a page and
> masked off that page when read/writing. This code has been here forever,
> but FIELD_PREP finds the bug when converted to use it. Change the code
> to do exactly the same thing but allow the conversion to FIELD_PREP in a
> later patch. To make it clear what we lost when making this change I
> left a comment, but there is no point to change the code to generate a
> correct sequence at this point.

:)

> This is not a Fixes tagged patch on purpose because it doesn't change
> the binary output.
> 
> Reviewed-by: Marcin Szycik <marcin.szycik@linux.intel.com>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/e1000e/80003es2lan.c b/drivers/net/ethernet/intel/e1000e/80003es2lan.c
index be9c695dde12..74671201208e 100644
--- a/drivers/net/ethernet/intel/e1000e/80003es2lan.c
+++ b/drivers/net/ethernet/intel/e1000e/80003es2lan.c
@@ -1035,17 +1035,18 @@  static s32 e1000_setup_copper_link_80003es2lan(struct e1000_hw *hw)
 	 * iteration and increase the max iterations when
 	 * polling the phy; this fixes erroneous timeouts at 10Mbps.
 	 */
-	ret_val = e1000_write_kmrn_reg_80003es2lan(hw, GG82563_REG(0x34, 4),
-						   0xFFFF);
+	/* these next three accesses were always meant to use page 0x34 using
+	 * GG82563_REG(0x34, N) but never did, so we've just corrected the call
+	 * to not drop bits
+	 */
+	ret_val = e1000_write_kmrn_reg_80003es2lan(hw, 4, 0xFFFF);
 	if (ret_val)
 		return ret_val;
-	ret_val = e1000_read_kmrn_reg_80003es2lan(hw, GG82563_REG(0x34, 9),
-						  &reg_data);
+	ret_val = e1000_read_kmrn_reg_80003es2lan(hw, 9, &reg_data);
 	if (ret_val)
 		return ret_val;
 	reg_data |= 0x3F;
-	ret_val = e1000_write_kmrn_reg_80003es2lan(hw, GG82563_REG(0x34, 9),
-						   reg_data);
+	ret_val = e1000_write_kmrn_reg_80003es2lan(hw, 9, reg_data);
 	if (ret_val)
 		return ret_val;
 	ret_val =