From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00124C433FE for ; Mon, 15 Nov 2021 09:21:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7F2763217 for ; Mon, 15 Nov 2021 09:21:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236431AbhKOJYK (ORCPT ); Mon, 15 Nov 2021 04:24:10 -0500 Received: from mx1.tq-group.com ([93.104.207.81]:45337 "EHLO mx1.tq-group.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236638AbhKOJX6 (ORCPT ); Mon, 15 Nov 2021 04:23:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1636968063; x=1668504063; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=7+q5wOUq3ntaAvVRKhGKpGVjQieDwZAsdV21wJvDGe8=; b=jV/RPWlW+DobyRIOZ+U6VaqCnybBOAHBC31ZY1peJ5ZCg5b0ldTQaxVk YkEOc8f9z+K8EW6G3Qp5aeatoz4yK0mbSNaMqPzcdcT0EpeaCGCqwcrZQ UuqT0kvJQ/tuK4CKPiPAWk9qtfQYcWtSCK3cV4VS1i7L+4DDXTLGljMdC sOUcM1by/Uej/eZavcJFr+sqr+7mpXlk/miSxRbV8BJCugwjVhl/8Oi0M lT9kDYgSNJg4iHbBrlz+bM0c0ubziH4ahC+lYrOxrrOHvJz5InR/JGpaN CUqXDQ7RlqVuxHH3842eFfuSENI/M+z0Br6D7vxPjj+xLmFL+gKP0Wgin w==; X-IronPort-AV: E=Sophos;i="5.87,236,1631570400"; d="scan'208";a="20459398" Received: from unknown (HELO tq-pgp-pr1.tq-net.de) ([192.168.6.15]) by mx1-pgp.tq-group.com with ESMTP; 15 Nov 2021 10:20:19 +0100 Received: from mx1.tq-group.com ([192.168.6.7]) by tq-pgp-pr1.tq-net.de (PGP Universal service); Mon, 15 Nov 2021 10:20:19 +0100 X-PGP-Universal: processed; by tq-pgp-pr1.tq-net.de on Mon, 15 Nov 2021 10:20:19 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1636968019; x=1668504019; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=7+q5wOUq3ntaAvVRKhGKpGVjQieDwZAsdV21wJvDGe8=; b=me7vdP7UgpW0m6fTZt9K17MMH0JXBBo5v34HGQ9nhmTbe5Il8YLpoaj8 OAOV2xuoe1DeQ/Y6jdhambzQG8WEOJWDvHSxJua2YihV40gAgr9tPjwui LAxM/LhMluBIjyR2TTmAoRjO/e9Fju5PTREXmmryrPSan72sTUX0zKicM 9T7lYEMZOekB2/IkvzakDMTbRWHCXViLYQ+KbAKU9kON1DGXZeCDXRmaY kv4jN9gIp6UyK1DNajXFYiIBjNBfTwu6HO8Qx62vIi1UZVBkRXjCjGppW ypGRnr4ZyQRRSOOGu8ViiEQBivL2J9c9XL0tugyWprQSX4coyHRaVKNjY A==; X-IronPort-AV: E=Sophos;i="5.87,236,1631570400"; d="scan'208";a="20459397" Received: from vtuxmail01.tq-net.de ([10.115.0.20]) by mx1.tq-group.com with ESMTP; 15 Nov 2021 10:20:19 +0100 Received: from schifferm-ubuntu4.tq-net.de (schifferm-ubuntu4.tq-net.de [10.121.48.12]) by vtuxmail01.tq-net.de (Postfix) with ESMTPA id 8B74428007F; Mon, 15 Nov 2021 10:20:19 +0100 (CET) From: Matthias Schiffer To: Chandrasekar Ramakrishnan , Wolfgang Grandegger , Marc Kleine-Budde Cc: "David S. Miller" , Jakub Kicinski , "Felipe Balbi (Intel)" , Jarkko Nikula , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Matthias Schiffer Subject: [PATCH net 4/4] can: m_can: pci: use custom bit timings for Elkhart Lake Date: Mon, 15 Nov 2021 10:18:52 +0100 Message-Id: <9eba5d7c05a48ead4024ffa6e5926f191d8c6b38.1636967198.git.matthias.schiffer@ew.tq-group.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The relevant datasheet [1] specifies nonstandard limits for the bit timing parameters. While it is unclear what the exact effect of violating these limits is, it seems like a good idea to adhere to the documentation. [1] Intel Atom® x6000E Series, and Intel® Pentium® and Celeron® N and J Series Processors for IoT Applications Datasheet, Volume 2 (Book 3 of 3), July 2021, Revision 001 Fixes: cab7ffc0324f ("can: m_can: add PCI glue driver for Intel Elkhart Lake") Signed-off-by: Matthias Schiffer --- drivers/net/can/m_can/m_can_pci.c | 48 ++++++++++++++++++++++++++++--- 1 file changed, 44 insertions(+), 4 deletions(-) diff --git a/drivers/net/can/m_can/m_can_pci.c b/drivers/net/can/m_can/m_can_pci.c index d3c030a13cbe..8bbbaa264f0d 100644 --- a/drivers/net/can/m_can/m_can_pci.c +++ b/drivers/net/can/m_can/m_can_pci.c @@ -18,9 +18,14 @@ #define M_CAN_PCI_MMIO_BAR 0 -#define M_CAN_CLOCK_FREQ_EHL 200000000 #define CTL_CSR_INT_CTL_OFFSET 0x508 +struct m_can_pci_config { + const struct can_bittiming_const *bit_timing; + const struct can_bittiming_const *data_timing; + unsigned int clock_freq; +}; + struct m_can_pci_priv { struct m_can_classdev cdev; @@ -74,9 +79,40 @@ static struct m_can_ops m_can_pci_ops = { .read_fifo = iomap_read_fifo, }; +static const struct can_bittiming_const m_can_bittiming_const_ehl = { + .name = KBUILD_MODNAME, + .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ + .tseg1_max = 64, + .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ + .tseg2_max = 128, + .sjw_max = 128, + .brp_min = 1, + .brp_max = 512, + .brp_inc = 1, +}; + +static const struct can_bittiming_const m_can_data_bittiming_const_ehl = { + .name = KBUILD_MODNAME, + .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ + .tseg1_max = 16, + .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ + .tseg2_max = 8, + .sjw_max = 4, + .brp_min = 1, + .brp_max = 32, + .brp_inc = 1, +}; + +static const struct m_can_pci_config m_can_pci_ehl = { + .bit_timing = &m_can_bittiming_const_ehl, + .data_timing = &m_can_data_bittiming_const_ehl, + .clock_freq = 200000000, +}; + static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id) { struct device *dev = &pci->dev; + const struct m_can_pci_config *cfg; struct m_can_classdev *mcan_class; struct m_can_pci_priv *priv; void __iomem *base; @@ -104,6 +140,8 @@ static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id) if (!mcan_class) return -ENOMEM; + cfg = (const struct m_can_pci_config *)id->driver_data; + priv = cdev_to_priv(mcan_class); priv->base = base; @@ -115,7 +153,9 @@ static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id) mcan_class->dev = &pci->dev; mcan_class->net->irq = pci_irq_vector(pci, 0); mcan_class->pm_clock_support = 1; - mcan_class->can.clock.freq = id->driver_data; + mcan_class->bit_timing = cfg->bit_timing; + mcan_class->data_timing = cfg->data_timing; + mcan_class->can.clock.freq = cfg->clock_freq; mcan_class->ops = &m_can_pci_ops; pci_set_drvdata(pci, mcan_class); @@ -168,8 +208,8 @@ static SIMPLE_DEV_PM_OPS(m_can_pci_pm_ops, m_can_pci_suspend, m_can_pci_resume); static const struct pci_device_id m_can_pci_id_table[] = { - { PCI_VDEVICE(INTEL, 0x4bc1), M_CAN_CLOCK_FREQ_EHL, }, - { PCI_VDEVICE(INTEL, 0x4bc2), M_CAN_CLOCK_FREQ_EHL, }, + { PCI_VDEVICE(INTEL, 0x4bc1), (kernel_ulong_t)&m_can_pci_ehl, }, + { PCI_VDEVICE(INTEL, 0x4bc2), (kernel_ulong_t)&m_can_pci_ehl, }, { } /* Terminating Entry */ }; MODULE_DEVICE_TABLE(pci, m_can_pci_id_table); -- 2.17.1