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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Sasha Levin <sashal@kernel.org>,
	linux-pci@vger.kernel.org
Subject: [PATCH AUTOSEL 6.6 13/31] PCI: Fix 64GT/s effective data rate calculation
Date: Sun, 28 Jan 2024 11:12:43 -0500
Message-ID: <20240128161315.201999-13-sashal@kernel.org>
In-Reply-To: <20240128161315.201999-1-sashal@kernel.org>
References: <20240128161315.201999-1-sashal@kernel.org>
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From: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

[ Upstream commit ac4f1897fa5433a1b07a625503a91b6aa9d7e643 ]

Unlike the lower rates, the PCIe 64GT/s Data Rate uses 1b/1b encoding, not
128b/130b (PCIe r6.1 sec 1.2, Table 1-1).  Correct the PCIE_SPEED2MBS_ENC()
calculation to reflect that.

Link: https://lore.kernel.org/r/20240102172701.65501-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/pci.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 5484048f457d..99abc4cec0df 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -269,7 +269,7 @@ void pci_bus_put(struct pci_bus *bus);
 
 /* PCIe speed to Mb/s reduced by encoding overhead */
 #define PCIE_SPEED2MBS_ENC(speed) \
-	((speed) == PCIE_SPEED_64_0GT ? 64000*128/130 : \
+	((speed) == PCIE_SPEED_64_0GT ? 64000*1/1 : \
 	 (speed) == PCIE_SPEED_32_0GT ? 32000*128/130 : \
 	 (speed) == PCIE_SPEED_16_0GT ? 16000*128/130 : \
 	 (speed) == PCIE_SPEED_8_0GT  ?  8000*128/130 : \
-- 
2.43.0