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From:   Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
To:     Jason Gunthorpe <jgg@ziepe.ca>, Joerg Roedel <jroedel@suse.de>,
        Lu Baolu <baolu.lu@linux.intel.com>, iommu@lists.linux.dev,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Cc:     Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Heiner Kallweit <hkallweit1@gmail.com>, nic_swsd@realtek.com,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>,
        Marco Elver <elver@google.com>
Subject: [PATCH v5 6/7] r8169: Coalesce mac ocp write and modify for 8125 and 8125B start to reduce spinlocks
Date:   Sun, 29 Oct 2023 19:36:05 +0100
Message-Id: <20231029183600.451694-6-mirsad.todorovac@alu.unizg.hr>
In-Reply-To: <20231029183600.451694-1-mirsad.todorovac@alu.unizg.hr>
References: <20231029183600.451694-1-mirsad.todorovac@alu.unizg.hr>
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Repeated calls to r8168_mac_ocp_write() and r8168_mac_ocp_modify() in
the startup of 8125 and 8125B involve implicit spin_lock_irqsave() and
spin_unlock_irqrestore() on each invocation.

Coalesced with the corresponding helpers r8168_mac_ocp_write_seq() and
r8168_mac_ocp_modify_seq() into sequential write or modidy with a sinqle
pair of spin_lock_irqsave() and spin_unlock_irqrestore(), these calls
reduce overall lock contention.

Fixes: f1bce4ad2f1ce ("r8169: add support for RTL8125")
Fixes: 0439297be9511 ("r8169: add support for RTL8125B")
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Marco Elver <elver@google.com>
Cc: nic_swsd@realtek.com
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/lkml/20231028005153.2180411-1-mirsad.todorovac@alu.unizg.hr/
Link: https://lore.kernel.org/lkml/20231028110459.2644926-1-mirsad.todorovac@alu.unizg.hr/
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
---
v5:
 added unlocked primitives to allow mac ocs modify grouping
 applied coalescing of mac ocp writes/modifies for 8168ep and 8117
 some formatting fixes to please checkpatch.pl

v4:
 fixed complaints as advised by Heiner and checkpatch.pl
 split the patch into five sections to be more easily manipulated and reviewed
 introduced r8168_mac_ocp_write_seq()
 applied coalescing of mac ocp writes/modifies for 8168H, 8125 and 8125B

v3:
 removed register/mask pair array sentinels, so using ARRAY_SIZE().
 avoided duplication of RTL_W32() call code as advised by Heiner.

 drivers/net/ethernet/realtek/r8169_main.c | 75 +++++++++++++----------
 1 file changed, 44 insertions(+), 31 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 50fbacb05953..0778cd0ba2e0 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -3553,6 +3553,28 @@ DECLARE_RTL_COND(rtl_mac_ocp_e00e_cond)
 
 static void rtl_hw_start_8125_common(struct rtl8169_private *tp)
 {
+	static const struct e_info_regmaskset e_info_8125_common_1[] = {
+		{ 0xd3e2, 0x0fff, 0x03a9 },
+		{ 0xd3e4, 0x00ff, 0x0000 },
+		{ 0xe860, 0x0000, 0x0080 },
+	};
+
+	static const struct e_info_regmaskset e_info_8125_common_2[] = {
+		{ 0xc0b4, 0x0000, 0x000c },
+		{ 0xeb6a, 0x00ff, 0x0033 },
+		{ 0xeb50, 0x03e0, 0x0040 },
+		{ 0xe056, 0x00f0, 0x0030 },
+		{ 0xe040, 0x1000, 0x0000 },
+		{ 0xea1c, 0x0003, 0x0001 },
+		{ 0xe0c0, 0x4f0f, 0x4403 },
+		{ 0xe052, 0x0080, 0x0068 },
+		{ 0xd430, 0x0fff, 0x047f },
+		{ 0xea1c, 0x0004, 0x0000 },
+		{ 0xeb54, 0x0000, 0x0001 },
+	};
+
+	unsigned long flags;
+
 	rtl_pcie_state_l2l3_disable(tp);
 
 	RTL_W16(tp, 0x382, 0x221b);
@@ -3560,47 +3582,38 @@ static void rtl_hw_start_8125_common(struct rtl8169_private *tp)
 	RTL_W16(tp, 0x4800, 0);
 
 	/* disable UPS */
-	r8168_mac_ocp_modify(tp, 0xd40a, 0x0010, 0x0000);
+
+	raw_spin_lock_irqsave(&tp->mac_ocp_lock, flags);
+	__r8168_mac_ocp_modify(tp, 0xd40a, 0x0010, 0x0000);
 
 	RTL_W8(tp, Config1, RTL_R8(tp, Config1) & ~0x10);
 
-	r8168_mac_ocp_write(tp, 0xc140, 0xffff);
-	r8168_mac_ocp_write(tp, 0xc142, 0xffff);
+	__r8168_mac_ocp_write(tp, 0xc140, 0xffff);
+	__r8168_mac_ocp_write(tp, 0xc142, 0xffff);
 
-	r8168_mac_ocp_modify(tp, 0xd3e2, 0x0fff, 0x03a9);
-	r8168_mac_ocp_modify(tp, 0xd3e4, 0x00ff, 0x0000);
-	r8168_mac_ocp_modify(tp, 0xe860, 0x0000, 0x0080);
+	__r8168_mac_ocp_modify_seq(tp, e_info_8125_common_1);
 
 	/* disable new tx descriptor format */
-	r8168_mac_ocp_modify(tp, 0xeb58, 0x0001, 0x0000);
+	__r8168_mac_ocp_modify(tp, 0xeb58, 0x0001, 0x0000);
 
-	if (tp->mac_version == RTL_GIGA_MAC_VER_63)
-		r8168_mac_ocp_modify(tp, 0xe614, 0x0700, 0x0200);
-	else
-		r8168_mac_ocp_modify(tp, 0xe614, 0x0700, 0x0400);
+	if (tp->mac_version == RTL_GIGA_MAC_VER_63) {
+		__r8168_mac_ocp_modify(tp, 0xe614, 0x0700, 0x0200);
+		__r8168_mac_ocp_modify(tp, 0xe63e, 0x0c30, 0x0000);
+	} else {
+		__r8168_mac_ocp_modify(tp, 0xe614, 0x0700, 0x0400);
+		__r8168_mac_ocp_modify(tp, 0xe63e, 0x0c30, 0x0020);
+	}
+
+	__r8168_mac_ocp_modify_seq(tp, e_info_8125_common_2);
+	raw_spin_unlock_irqrestore(&tp->mac_ocp_lock, flags);
 
-	if (tp->mac_version == RTL_GIGA_MAC_VER_63)
-		r8168_mac_ocp_modify(tp, 0xe63e, 0x0c30, 0x0000);
-	else
-		r8168_mac_ocp_modify(tp, 0xe63e, 0x0c30, 0x0020);
-
-	r8168_mac_ocp_modify(tp, 0xc0b4, 0x0000, 0x000c);
-	r8168_mac_ocp_modify(tp, 0xeb6a, 0x00ff, 0x0033);
-	r8168_mac_ocp_modify(tp, 0xeb50, 0x03e0, 0x0040);
-	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0030);
-	r8168_mac_ocp_modify(tp, 0xe040, 0x1000, 0x0000);
-	r8168_mac_ocp_modify(tp, 0xea1c, 0x0003, 0x0001);
-	r8168_mac_ocp_modify(tp, 0xe0c0, 0x4f0f, 0x4403);
-	r8168_mac_ocp_modify(tp, 0xe052, 0x0080, 0x0068);
-	r8168_mac_ocp_modify(tp, 0xd430, 0x0fff, 0x047f);
-
-	r8168_mac_ocp_modify(tp, 0xea1c, 0x0004, 0x0000);
-	r8168_mac_ocp_modify(tp, 0xeb54, 0x0000, 0x0001);
 	udelay(1);
-	r8168_mac_ocp_modify(tp, 0xeb54, 0x0001, 0x0000);
-	RTL_W16(tp, 0x1880, RTL_R16(tp, 0x1880) & ~0x0030);
 
-	r8168_mac_ocp_write(tp, 0xe098, 0xc302);
+	raw_spin_lock_irqsave(&tp->mac_ocp_lock, flags);
+	__r8168_mac_ocp_modify(tp, 0xeb54, 0x0001, 0x0000);
+	RTL_W16(tp, 0x1880, RTL_R16(tp, 0x1880) & ~0x0030);
+	__r8168_mac_ocp_write(tp, 0xe098, 0xc302);
+	raw_spin_unlock_irqrestore(&tp->mac_ocp_lock, flags);
 
 	rtl_loop_wait_low(tp, &rtl_mac_ocp_e00e_cond, 1000, 10);
 
-- 
2.34.1