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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DD15C433F5 for ; Mon, 20 Dec 2021 15:18:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237432AbhLTPS3 (ORCPT ); Mon, 20 Dec 2021 10:18:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238232AbhLTPRR (ORCPT ); Mon, 20 Dec 2021 10:17:17 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66A15C00FC6B; Mon, 20 Dec 2021 06:58:22 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 057B3611A4; Mon, 20 Dec 2021 14:58:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1201AC36AE8; Mon, 20 Dec 2021 14:58:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640012301; bh=clAaQzTP0rMW5OwhF8ndOEhvFQnKygyf7ZxblxVQXMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xnMLQMI9Oh+uRaAU44XS/LSBosONId3bN1s4Ry9yilrZqcMv7A0JUxe7wpNDCRU1a +s9VgRPh8K3/kJKFD42Xb7y/49fqH6Ks0yMHXQ/NS664HF1CN53cMglpHFNilz+QcT faaQgtF9EV9YO8KBD6/eAerGGW1soZ7+J0g2S52g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Matthias Schiffer , Marc Kleine-Budde Subject: [PATCH 5.15 153/177] can: m_can: pci: use custom bit timings for Elkhart Lake Date: Mon, 20 Dec 2021 15:35:03 +0100 Message-Id: <20211220143045.226729826@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211220143040.058287525@linuxfoundation.org> References: <20211220143040.058287525@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Matthias Schiffer commit ea4c1787685dbf9842046f05b6390b6901ee6ba2 upstream. 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") Link: https://lore.kernel.org/all/9eba5d7c05a48ead4024ffa6e5926f191d8c6b38.1636967198.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Matthias Schiffer Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/m_can/m_can_pci.c | 48 ++++++++++++++++++++++++++++++++++---- 1 file changed, 44 insertions(+), 4 deletions(-) --- 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; @@ -84,9 +89,40 @@ 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; @@ -114,6 +150,8 @@ static int m_can_pci_probe(struct pci_de if (!mcan_class) return -ENOMEM; + cfg = (const struct m_can_pci_config *)id->driver_data; + priv = cdev_to_priv(mcan_class); priv->base = base; @@ -125,7 +163,9 @@ static int m_can_pci_probe(struct pci_de 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); @@ -178,8 +218,8 @@ static SIMPLE_DEV_PM_OPS(m_can_pci_pm_op 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);