diff mbox series

[RFC,net-next] net: phy: marvell: add comment about m88e1111_config_init_1000basex()

Message ID E1rezry-003cXf-5f@rmk-PC.armlinux.org.uk (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [RFC,net-next] net: phy: marvell: add comment about m88e1111_config_init_1000basex() | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 940 this patch: 940
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 957 this patch: 957
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 957 this patch: 957
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 11 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Russell King (Oracle) Feb. 27, 2024, 3:59 p.m. UTC 
The comment in m88e1111_config_init_1000basex() is wrong - it claims
that Autoneg will be enabled, but this doesn't actually happen.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
The 88E1111 datasheet says that when changing HWCFG to 1100 (1000base-X
no AN) then one also needs to clear bit 12 in the fibre BMCR.
Furthermore, it says that in the Mode Switching chapter that when
switching the mode between 1000 and 1100, bit 12 of the fibre BMCR needs
to be manually updated.

However, the 88E1111 code doesn't do this, it just changes HWCFG and then
seems to hope for the best. Is this something which should be fixed?

 drivers/net/phy/marvell.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index 1faa22f58366..42ed013385bf 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -919,7 +919,10 @@  static int m88e1111_config_init_1000basex(struct phy_device *phydev)
 	if (extsr < 0)
 		return extsr;
 
-	/* If using copper mode, ensure 1000BaseX auto-negotiation is enabled */
+	/* If using copper mode, ensure 1000BaseX auto-negotiation is enabled.
+	 * FIXME: this does not actually enable 1000BaseX auto-negotiation if
+	 * it was previously disabled in the Fiber BMCR!
+	 */
 	mode = extsr & MII_M1111_HWCFG_MODE_MASK;
 	if (mode == MII_M1111_HWCFG_MODE_COPPER_1000X_NOAN) {
 		err = phy_modify(phydev, MII_M1111_PHY_EXT_SR,