From: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
To: Felix Fietkau <nbd@nbd.name>, John Crispin <john@phrozen.org>,
Sean Wang <sean.wang@mediatek.com>,
Mark Lee <Mark-MC.Lee@mediatek.com>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Matthias Brugger <matthias.bgg@gmail.com>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org
Cc: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
Subject: [PATCH net-next v2 10/15] net: ethernet: mtk_eth_soc: cache HW pointer of last freed TX descriptor
Date: Thu, 22 Apr 2021 22:21:03 -0700 [thread overview]
Message-ID: <20210423052108.423853-11-ilya.lipnitskiy@gmail.com> (raw)
In-Reply-To: <20210423052108.423853-1-ilya.lipnitskiy@gmail.com>
From: Felix Fietkau <nbd@nbd.name>
The value is only updated by the CPU, so it is cheaper to access from the
ring data structure than from a hardware register.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 8 ++++----
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 2 ++
2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 762e985fa294..6d23118b7a6c 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1364,7 +1364,7 @@ static int mtk_poll_tx_qdma(struct mtk_eth *eth, int budget,
struct mtk_tx_buf *tx_buf;
u32 cpu, dma;
- cpu = mtk_r32(eth, MTK_QTX_CRX_PTR);
+ cpu = ring->last_free_ptr;
dma = mtk_r32(eth, MTK_QTX_DRX_PTR);
desc = mtk_qdma_phys_to_virt(ring, cpu);
@@ -1398,6 +1398,7 @@ static int mtk_poll_tx_qdma(struct mtk_eth *eth, int budget,
cpu = next_cpu;
}
+ ring->last_free_ptr = cpu;
mtk_w32(eth, cpu, MTK_QTX_CRX_PTR);
return budget;
@@ -1598,6 +1599,7 @@ static int mtk_tx_alloc(struct mtk_eth *eth)
atomic_set(&ring->free_count, MTK_DMA_SIZE - 2);
ring->next_free = &ring->dma[0];
ring->last_free = &ring->dma[MTK_DMA_SIZE - 1];
+ ring->last_free_ptr = (u32)(ring->phys + ((MTK_DMA_SIZE - 1) * sz));
ring->thresh = MAX_SKB_FRAGS;
/* make sure that all changes to the dma ring are flushed before we
@@ -1611,9 +1613,7 @@ static int mtk_tx_alloc(struct mtk_eth *eth)
mtk_w32(eth,
ring->phys + ((MTK_DMA_SIZE - 1) * sz),
MTK_QTX_CRX_PTR);
- mtk_w32(eth,
- ring->phys + ((MTK_DMA_SIZE - 1) * sz),
- MTK_QTX_DRX_PTR);
+ mtk_w32(eth, ring->last_free_ptr, MTK_QTX_DRX_PTR);
mtk_w32(eth, (QDMA_RES_THRES << 8) | QDMA_RES_THRES,
MTK_QTX_CFG(0));
} else {
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index ceb5a4a661e6..6b92dd6c2cda 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -642,6 +642,7 @@ struct mtk_tx_buf {
* @phys: The physical addr of tx_buf
* @next_free: Pointer to the next free descriptor
* @last_free: Pointer to the last free descriptor
+ * @last_free_ptr: Hardware pointer value of the last free descriptor
* @thresh: The threshold of minimum amount of free descriptors
* @free_count: QDMA uses a linked list. Track how many free descriptors
* are present
@@ -652,6 +653,7 @@ struct mtk_tx_ring {
dma_addr_t phys;
struct mtk_tx_dma *next_free;
struct mtk_tx_dma *last_free;
+ u32 last_free_ptr;
u16 thresh;
atomic_t free_count;
int dma_size;
--
2.31.1
next prev parent reply other threads:[~2021-04-23 5:22 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-23 5:20 [PATCH net-next v2 00/15] mtk_eth_soc: fixes and performance improvements Ilya Lipnitskiy
2021-04-23 5:20 ` [PATCH net-next v2 01/15] net: ethernet: mtk_eth_soc: fix RX VLAN offload Ilya Lipnitskiy
2021-04-23 5:20 ` [PATCH net-next v2 02/15] net: ethernet: mtk_eth_soc: unmap RX data before calling build_skb Ilya Lipnitskiy
2021-04-23 5:20 ` [PATCH net-next v2 03/15] net: ethernet: mtk_eth_soc: fix build_skb cleanup Ilya Lipnitskiy
2021-04-23 5:20 ` [PATCH net-next v2 04/15] net: ethernet: mtk_eth_soc: use napi_consume_skb Ilya Lipnitskiy
2021-04-23 5:20 ` [PATCH net-next v2 05/15] net: ethernet: mtk_eth_soc: reduce MDIO bus access latency Ilya Lipnitskiy
2021-04-23 5:20 ` [PATCH net-next v2 06/15] net: ethernet: mtk_eth_soc: remove unnecessary TX queue stops Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 07/15] net: ethernet: mtk_eth_soc: use larger burst size for QDMA TX Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 08/15] net: ethernet: mtk_eth_soc: increase DMA ring sizes Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 09/15] net: ethernet: mtk_eth_soc: implement dynamic interrupt moderation Ilya Lipnitskiy
2021-04-23 5:21 ` Ilya Lipnitskiy [this message]
2021-04-23 5:21 ` [PATCH net-next v2 11/15] net: ethernet: mtk_eth_soc: only read the full RX descriptor if DMA is done Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 12/15] net: ethernet: mtk_eth_soc: reduce unnecessary interrupts Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 13/15] net: ethernet: mtk_eth_soc: rework NAPI callbacks Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 14/15] net: ethernet: mtk_eth_soc: set PPE flow hash as skb hash if present Ilya Lipnitskiy
2021-04-23 5:21 ` [PATCH net-next v2 15/15] net: ethernet: mtk_eth_soc: use iopoll.h macro for DMA init Ilya Lipnitskiy
2021-04-23 21:00 ` [PATCH net-next v2 00/15] mtk_eth_soc: fixes and performance improvements patchwork-bot+netdevbpf
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210423052108.423853-11-ilya.lipnitskiy@gmail.com \
--to=ilya.lipnitskiy@gmail.com \
--cc=Mark-MC.Lee@mediatek.com \
--cc=davem@davemloft.net \
--cc=john@phrozen.org \
--cc=kuba@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=nbd@nbd.name \
--cc=netdev@vger.kernel.org \
--cc=sean.wang@mediatek.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).