From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753433AbdDJMvc (ORCPT ); Mon, 10 Apr 2017 08:51:32 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:39207 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752750AbdDJMv3 (ORCPT ); Mon, 10 Apr 2017 08:51:29 -0400 Subject: Re: [PATCH v7 3/6] watchdog: iTCO_wdt: cleanup set/unset no_reboot_bit functions To: Kuppuswamy Sathyanarayanan , andy@infradead.org, qipeng.zha@intel.com, dvhart@infradead.org References: Cc: wim@iguana.be, sathyaosid@gmail.com, david.e.box@linux.intel.com, rajneesh.bhardwaj@intel.com, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, linux-watchdog@vger.kernel.org From: Guenter Roeck Message-ID: Date: Mon, 10 Apr 2017 05:51:26 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/09/2017 03:00 PM, Kuppuswamy Sathyanarayanan wrote: > iTCO_wdt no_reboot_bit set/unset functions has lot of common code between > them. So merging these two functions into a single update function would > remove these unnecessary code duplications. This patch fixes this issue > by creating a no_reboot_bit update function to handle both set/unset > functions. > > Also checking for iTCO version every time you make no_reboot_bit set/unset > call is inefficient and makes the code look complex. This can be improved > by performing this check once during device probe and selecting the > appropriate no_reboot_bit update function. This patch fixes this issue > by splitting the update function into multiple helper functions. > > Signed-off-by: Kuppuswamy Sathyanarayanan Reviewed-by: Guenter Roeck > --- > drivers/watchdog/iTCO_wdt.c | 83 +++++++++++++++++++++++++++------------------ > 1 file changed, 50 insertions(+), 33 deletions(-) > > Changes since v6: > * make iTCO_wdt_no_reboot_bit_setup() static > * remove inline specifier for update_no_reboot_bit helper functions. > > Changes since v5: > * Changed update function argument name from "status" to "set". > * Fixed commit history. > * Changed update function name to use "bit" instead of "flag" > * Addressed Andy's comment on creating multiple helper functions. > > diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c > index 3d0abc0..a629933 100644 > --- a/drivers/watchdog/iTCO_wdt.c > +++ b/drivers/watchdog/iTCO_wdt.c > @@ -106,6 +106,8 @@ struct iTCO_wdt_private { > struct pci_dev *pci_dev; > /* whether or not the watchdog has been suspended */ > bool suspended; > + /* no reboot update function pointer */ > + int (*update_no_reboot_bit)(void *p, bool set); > }; > > /* module parameters */ > @@ -170,48 +172,61 @@ static inline u32 no_reboot_bit(struct iTCO_wdt_private *p) > return enable_bit; > } > > -static void iTCO_wdt_set_NO_REBOOT_bit(struct iTCO_wdt_private *p) > +static int update_no_reboot_bit_def(void *priv, bool set) > { > - u32 val32; > - > - /* Set the NO_REBOOT bit: this disables reboots */ > - if (p->iTCO_version >= 2) { > - val32 = readl(p->gcs_pmc); > - val32 |= no_reboot_bit(p); > - writel(val32, p->gcs_pmc); > - } else if (p->iTCO_version == 1) { > - pci_read_config_dword(p->pci_dev, 0xd4, &val32); > - val32 |= no_reboot_bit(p); > - pci_write_config_dword(p->pci_dev, 0xd4, val32); > - } > + return 0; > } > > -static int iTCO_wdt_unset_NO_REBOOT_bit(struct iTCO_wdt_private *p) > +static int update_no_reboot_bit_pci(void *priv, bool set) > { > - u32 enable_bit = no_reboot_bit(p); > - u32 val32 = 0; > + struct iTCO_wdt_private *p = priv; > + u32 val32 = 0, newval32 = 0; > > - /* Unset the NO_REBOOT bit: this enables reboots */ > - if (p->iTCO_version >= 2) { > - val32 = readl(p->gcs_pmc); > - val32 &= ~enable_bit; > - writel(val32, p->gcs_pmc); > + pci_read_config_dword(p->pci_dev, 0xd4, &val32); > + if (set) > + val32 |= no_reboot_bit(p); > + else > + val32 &= ~no_reboot_bit(p); > + pci_write_config_dword(p->pci_dev, 0xd4, val32); > + pci_read_config_dword(p->pci_dev, 0xd4, &newval32); > > - val32 = readl(p->gcs_pmc); > - } else if (p->iTCO_version == 1) { > - pci_read_config_dword(p->pci_dev, 0xd4, &val32); > - val32 &= ~enable_bit; > - pci_write_config_dword(p->pci_dev, 0xd4, val32); > + /* make sure the update is successful */ > + if (val32 != newval32) > + return -EIO; > > - pci_read_config_dword(p->pci_dev, 0xd4, &val32); > - } > + return 0; > +} > + > +static int update_no_reboot_bit_mem(void *priv, bool set) > +{ > + struct iTCO_wdt_private *p = priv; > + u32 val32 = 0, newval32 = 0; > + > + val32 = readl(p->gcs_pmc); > + if (set) > + val32 |= no_reboot_bit(p); > + else > + val32 &= ~no_reboot_bit(p); > + writel(val32, p->gcs_pmc); > + newval32 = readl(p->gcs_pmc); > > - if (val32 & enable_bit) > + /* make sure the update is successful */ > + if (val32 != newval32) > return -EIO; > > return 0; > } > > +static void iTCO_wdt_no_reboot_bit_setup(struct iTCO_wdt_private *p) > +{ > + if (p->iTCO_version >= 2) > + p->update_no_reboot_bit = update_no_reboot_bit_mem; > + else if (p->iTCO_version == 1) > + p->update_no_reboot_bit = update_no_reboot_bit_pci; > + else > + p->update_no_reboot_bit = update_no_reboot_bit_def; > +} > + > static int iTCO_wdt_start(struct watchdog_device *wd_dev) > { > struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); > @@ -222,7 +237,7 @@ static int iTCO_wdt_start(struct watchdog_device *wd_dev) > iTCO_vendor_pre_start(p->smi_res, wd_dev->timeout); > > /* disable chipset's NO_REBOOT bit */ > - if (iTCO_wdt_unset_NO_REBOOT_bit(p)) { > + if (p->update_no_reboot_bit(p, false)) { > spin_unlock(&p->io_lock); > pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n"); > return -EIO; > @@ -263,7 +278,7 @@ static int iTCO_wdt_stop(struct watchdog_device *wd_dev) > val = inw(TCO1_CNT(p)); > > /* Set the NO_REBOOT bit to prevent later reboots, just for sure */ > - iTCO_wdt_set_NO_REBOOT_bit(p); > + p->update_no_reboot_bit(p, true); > > spin_unlock(&p->io_lock); > > @@ -428,6 +443,8 @@ static int iTCO_wdt_probe(struct platform_device *pdev) > p->iTCO_version = pdata->version; > p->pci_dev = to_pci_dev(dev->parent); > > + iTCO_wdt_no_reboot_bit_setup(p); > + > /* > * Get the Memory-Mapped GCS or PMC register, we need it for the > * NO_REBOOT flag (TCO v2 and v3). > @@ -442,14 +459,14 @@ static int iTCO_wdt_probe(struct platform_device *pdev) > } > > /* Check chipset's NO_REBOOT bit */ > - if (iTCO_wdt_unset_NO_REBOOT_bit(p) && > + if (p->update_no_reboot_bit(p, false) && > iTCO_vendor_check_noreboot_on()) { > pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n"); > return -ENODEV; /* Cannot reset NO_REBOOT bit */ > } > > /* Set the NO_REBOOT bit to prevent later reboots, just for sure */ > - iTCO_wdt_set_NO_REBOOT_bit(p); > + p->update_no_reboot_bit(p, true); > > /* The TCO logic uses the TCO_EN bit in the SMI_EN register */ > if (!devm_request_region(dev, p->smi_res->start, >