| Message ID | 20250124101359.2926906-2-hayashi.kunihiko@socionext.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Limit devicetree parameters to hardware capability | expand |
On Fri, Jan 24, 2025 at 07:13:57PM +0900, Kunihiko Hayashi wrote: > The number of MTL queues to use is specified by the parameter > "snps,{tx,rx}-queues-to-use" from stmmac_platform layer. > > However, the maximum numbers of queues are constrained by upper limits > determined by the capability of each hardware feature. It's appropriate > to limit the values not to exceed the upper limit values and display > a warning message. > > This only works if the hardware capability has the upper limit values. > > Fixes: d976a525c371 ("net: stmmac: multiple queues dt configuration") > Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> > --- > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > index 7bf275f127c9..be1e6fa6d557 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > @@ -7232,6 +7232,21 @@ static int stmmac_hw_init(struct stmmac_priv *priv) > if (priv->dma_cap.tsoen) > dev_info(priv->device, "TSO supported\n"); > > + if (priv->dma_cap.number_rx_queues && > + priv->dma_cap.number_rx_queues < priv->plat->rx_queues_to_use) { While this looks "nicer", which of these two do you think reads better and is easier to understand: "If priv->dma_cap.number_rx_queues is set, and priv->dma_cap.number_rx_queues is less than priv->plat->rx_queues_to_use then print a message about priv->plat->rx_queues_to_use exceeding priv->dma_cap.number_rx_queues" "If priv->dma_cap.number_rx_queues is set, and priv->plat->rx_queues_to_use is greater than priv->dma_cap.number_rx_queues, then print a message about priv->plat->rx_queues_to_use exceeding priv->dma_cap.number_rx_queues" With the former one has to mentally flip the test around in the if statement to check that it does indeed match the warning that is printed.
On 2025/01/24 20:43, Russell King (Oracle) wrote: > On Fri, Jan 24, 2025 at 07:13:57PM +0900, Kunihiko Hayashi wrote: >> The number of MTL queues to use is specified by the parameter >> "snps,{tx,rx}-queues-to-use" from stmmac_platform layer. >> >> However, the maximum numbers of queues are constrained by upper limits >> determined by the capability of each hardware feature. It's appropriate >> to limit the values not to exceed the upper limit values and display >> a warning message. >> >> This only works if the hardware capability has the upper limit values. >> >> Fixes: d976a525c371 ("net: stmmac: multiple queues dt configuration") >> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> >> --- >> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 15 +++++++++++++++ >> 1 file changed, 15 insertions(+) >> >> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c >> index 7bf275f127c9..be1e6fa6d557 100644 >> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c >> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c >> @@ -7232,6 +7232,21 @@ static int stmmac_hw_init(struct stmmac_priv > *priv) >> if (priv->dma_cap.tsoen) >> dev_info(priv->device, "TSO supported\n"); >> >> + if (priv->dma_cap.number_rx_queues && >> + priv->dma_cap.number_rx_queues < priv->plat->rx_queues_to_use) > { > > While this looks "nicer", which of these two do you think reads better > and is easier to understand: > > "If priv->dma_cap.number_rx_queues is set, and > priv->dma_cap.number_rx_queues is less than > priv->plat->rx_queues_to_use then print a message about > priv->plat->rx_queues_to_use exceeding priv->dma_cap.number_rx_queues" > > "If priv->dma_cap.number_rx_queues is set, and > priv->plat->rx_queues_to_use is greater than > priv->dma_cap.number_rx_queues, then print a message about > priv->plat->rx_queues_to_use exceeding priv->dma_cap.number_rx_queues" > > With the former one has to mentally flip the test around in the if > statement to check that it does indeed match the warning that is > printed. This patch focuses only on the conditional lines, however, certainly it's not good to have the meaning of the message and the condition reversed. I'll fix it next. Thank you, --- Best Regards Kunihiko Hayashi
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 7bf275f127c9..be1e6fa6d557 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -7232,6 +7232,21 @@ static int stmmac_hw_init(struct stmmac_priv *priv) if (priv->dma_cap.tsoen) dev_info(priv->device, "TSO supported\n"); + if (priv->dma_cap.number_rx_queues && + priv->dma_cap.number_rx_queues < priv->plat->rx_queues_to_use) { + dev_warn(priv->device, + "Number of Rx queues (%u) exceeds dma capability\n", + priv->plat->rx_queues_to_use); + priv->plat->rx_queues_to_use = priv->dma_cap.number_rx_queues; + } + if (priv->dma_cap.number_tx_queues && + priv->dma_cap.number_tx_queues < priv->plat->tx_queues_to_use) { + dev_warn(priv->device, + "Number of Tx queues (%u) exceeds dma capability\n", + priv->plat->tx_queues_to_use); + priv->plat->tx_queues_to_use = priv->dma_cap.number_tx_queues; + } + priv->hw->vlan_fail_q_en = (priv->plat->flags & STMMAC_FLAG_VLAN_FAIL_Q_EN); priv->hw->vlan_fail_q = priv->plat->vlan_fail_q;
The number of MTL queues to use is specified by the parameter "snps,{tx,rx}-queues-to-use" from stmmac_platform layer. However, the maximum numbers of queues are constrained by upper limits determined by the capability of each hardware feature. It's appropriate to limit the values not to exceed the upper limit values and display a warning message. This only works if the hardware capability has the upper limit values. Fixes: d976a525c371 ("net: stmmac: multiple queues dt configuration") Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)