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 75C35C43217 for ; Tue, 7 Dec 2021 10:25:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235082AbhLGK2n (ORCPT ); Tue, 7 Dec 2021 05:28:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235118AbhLGK2e (ORCPT ); Tue, 7 Dec 2021 05:28:34 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ABD6DC061A83 for ; Tue, 7 Dec 2021 02:24:56 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1muXeZ-0003Qk-13 for linux-can@vger.kernel.org; Tue, 07 Dec 2021 11:24:55 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 1EFA36BE8F7 for ; Tue, 7 Dec 2021 10:24:48 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id 406B56BE8B5; Tue, 7 Dec 2021 10:24:44 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id ba47db34; Tue, 7 Dec 2021 10:24:27 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Matthias Schiffer , Marc Kleine-Budde Subject: [PATCH net 9/9] can: m_can: pci: use custom bit timings for Elkhart Lake Date: Tue, 7 Dec 2021 11:24:20 +0100 Message-Id: <20211207102420.120131-10-mkl@pengutronix.de> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211207102420.120131-1-mkl@pengutronix.de> References: <20211207102420.120131-1-mkl@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-can@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org From: Matthias Schiffer 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 --- 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 8f184a852a0a..b56a54d6c5a9 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; @@ -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_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; @@ -125,7 +163,9 @@ 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); @@ -178,8 +218,8 @@ 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); -- 2.33.0