diff mbox series

[net,v2,1/3] net: stmmac: Limit the number of MTL queues to hardware capability

Message ID 20250121044138.2883912-2-hayashi.kunihiko@socionext.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Limit devicetree parameters to hardware capability | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: linux-stm32@st-md-mailman.stormreply.com
netdev/build_clang success Errors and warnings before: 1 this patch: 1
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 Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 38 this patch: 38
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-01-21--12-00 (tests: 885)

Commit Message

Kunihiko Hayashi Jan. 21, 2025, 4:41 a.m. UTC
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.

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 | 13 +++++++++++++
 1 file changed, 13 insertions(+)

Comments

Furong Xu Jan. 21, 2025, 6:25 a.m. UTC | #1
On Tue, 21 Jan 2025 13:41:36 +0900, Kunihiko Hayashi <hayashi.kunihiko@socionext.com> 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.
> 
> 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 | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 7bf275f127c9..251a8c15637f 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -7232,6 +7232,19 @@ static int stmmac_hw_init(struct stmmac_priv *priv)
>  	if (priv->dma_cap.tsoen)
>  		dev_info(priv->device, "TSO supported\n");
>  
> +	if (priv->plat->rx_queues_to_use > priv->dma_cap.number_rx_queues) {
> +		dev_warn(priv->device,
> +			 "Number of Rx queues exceeds dma capability (%d)\n",
> +			 priv->plat->rx_queues_to_use);
> +		priv->plat->rx_queues_to_use = priv->dma_cap.number_rx_queues;
> +	}
> +	if (priv->plat->tx_queues_to_use > priv->dma_cap.number_tx_queues) {
> +		dev_warn(priv->device,
> +			 "Number of Tx queues exceeds dma capability (%d)\n",
> +			 priv->plat->tx_queues_to_use);

I would prefer print these warnings like this:

dev_warn(priv->device, "Number of Tx queues (%u) exceeds dma capability (%u)\n",
priv->plat->tx_queues_to_use, priv->dma_cap.number_tx_queues);

And number_tx_queues, number_rx_queues are u32, so %u would be better.

This print format change is quite minor. Probably not worth a re-roll since one
can always view DMA capabilities by reading a debugfs entry.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 7bf275f127c9..251a8c15637f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -7232,6 +7232,19 @@  static int stmmac_hw_init(struct stmmac_priv *priv)
 	if (priv->dma_cap.tsoen)
 		dev_info(priv->device, "TSO supported\n");
 
+	if (priv->plat->rx_queues_to_use > priv->dma_cap.number_rx_queues) {
+		dev_warn(priv->device,
+			 "Number of Rx queues exceeds dma capability (%d)\n",
+			 priv->plat->rx_queues_to_use);
+		priv->plat->rx_queues_to_use = priv->dma_cap.number_rx_queues;
+	}
+	if (priv->plat->tx_queues_to_use > priv->dma_cap.number_tx_queues) {
+		dev_warn(priv->device,
+			 "Number of Tx queues exceeds dma capability (%d)\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;