admin/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2025-12-07 20:06:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

net: stmmac: improve ndev->max_mtu setup readability

Browse Source 
Improve the readibility of the code setting ndev->max_mtu. This depends
on the hardware specific maximum defined by the MAC core, and also a
platform provided maximum.

The code was originally checking that the platform specific maximum was
between ndev->min_mtu..MAC core maximum before reducing ndev->max_mtu,
otherwise if the platform specific maximum was less than ndev->min_mtu,
issuing a warning.

Re-order the code to handle the case where the platform specific max is
below ndev->min_mtu, which then means that the subsequent test is
simply reducing ndev->max_mtu.

Update the comment, and add a few blank lines to separate the blocks of
code.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/E1vImWA-0000000DrIl-1HZY@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Russell King (Oracle)
2025-11-11 11:26:34 +00:00
committed by Jakub Kicinski
parent 1479493c91
commit 7e975caa0f
1 changed files with 12 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

22
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
View File

@@ -1392,9 +1392,9 @@ static unsigned int stmmac_rx_offset(struct stmmac_priv *priv)
return NET_SKB_PAD;
}
static int stmmac_set_bfsize(int mtu, int bufsize)
static int stmmac_set_bfsize(int mtu)
{
int ret = bufsize;
int ret;
if (mtu >= BUF_SIZE_8KiB)
ret = BUF_SIZE_16KiB;
@@ -3958,12 +3958,13 @@ stmmac_setup_dma_desc(struct stmmac_priv *priv, unsigned int mtu)
return ERR_PTR(-ENOMEM);
}
/* Returns 0 or BUF_SIZE_16KiB if mtu > 8KiB and dwmac4 or ring mode */
bfsize = stmmac_set_16kib_bfsize(priv, mtu);
if (bfsize < 0)
bfsize = 0;
if (bfsize < BUF_SIZE_16KiB)
bfsize = stmmac_set_bfsize(mtu, 0);
bfsize = stmmac_set_bfsize(mtu);
dma_conf->dma_buf_sz = bfsize;
/* Chose the tx/rx size from the already defined one in the
@@ -7773,22 +7774,23 @@ int stmmac_dvr_probe(struct device *device,
/* MTU range: 46 - hw-specific max */
ndev->min_mtu = ETH_ZLEN - ETH_HLEN;
if (priv->plat->core_type == DWMAC_CORE_XGMAC)
ndev->max_mtu = XGMAC_JUMBO_LEN;
else if ((priv->plat->enh_desc) || (priv->synopsys_id >= DWMAC_CORE_4_00))
else if (priv->plat->enh_desc || priv->synopsys_id >= DWMAC_CORE_4_00)
ndev->max_mtu = JUMBO_LEN;
else
ndev->max_mtu = SKB_MAX_HEAD(NET_SKB_PAD + NET_IP_ALIGN);
/* Will not overwrite ndev->max_mtu if plat->maxmtu > ndev->max_mtu
* as well as plat->maxmtu < ndev->min_mtu which is a invalid range.
/* Warn if the platform's maxmtu is smaller than the minimum MTU,
* otherwise clamp the maximum MTU above to the platform's maxmtu.
*/
if ((priv->plat->maxmtu < ndev->max_mtu) &&
(priv->plat->maxmtu >= ndev->min_mtu))
ndev->max_mtu = priv->plat->maxmtu;
else if (priv->plat->maxmtu < ndev->min_mtu)
if (priv->plat->maxmtu < ndev->min_mtu)
dev_warn(priv->device,
"%s: warning: maxmtu having invalid value (%d)\n",
__func__, priv->plat->maxmtu);
else if (priv->plat->maxmtu < ndev->max_mtu)
ndev->max_mtu = priv->plat->maxmtu;
ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;