From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 2/5] libata: implement sata_link_scr_lpm() and make ata_dev_set_feature() global Date: Wed, 1 Sep 2010 17:50:05 +0200 Message-ID: <1283356208-1884-3-git-send-email-tj@kernel.org> References: <1283356208-1884-1-git-send-email-tj@kernel.org> Return-path: Received: from hera.kernel.org ([140.211.167.34]:35951 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755897Ab0IAPu2 (ORCPT ); Wed, 1 Sep 2010 11:50:28 -0400 In-Reply-To: <1283356208-1884-1-git-send-email-tj@kernel.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: jeff@garzik.org, linux-ide@vger.kernel.org Cc: Tejun Heo Link power management is about to be reimplemented. Prepare for it. * Implement sata_link_scr_lpm(). * Drop static from ata_dev_set_feature() and make it available to other libata files. * Trivial whitespace adjustments. Signed-off-by: Tejun Heo --- drivers/ata/libata-core.c | 75 ++++++++++++++++++++++++++++++++++++++++++--- drivers/ata/libata.h | 2 + include/linux/libata.h | 2 + 3 files changed, 74 insertions(+), 5 deletions(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index a7274f5..c8573e0 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -91,8 +91,6 @@ const struct ata_port_operations sata_port_ops = { static unsigned int ata_dev_init_params(struct ata_device *dev, u16 heads, u16 sectors); static unsigned int ata_dev_set_xfermode(struct ata_device *dev); -static unsigned int ata_dev_set_feature(struct ata_device *dev, - u8 enable, u8 feature); static void ata_dev_xfermask(struct ata_device *dev); static unsigned long ata_dev_blacklisted(const struct ata_device *dev); @@ -3628,7 +3626,7 @@ int ata_wait_after_reset(struct ata_link *link, unsigned long deadline, * @params: timing parameters { interval, duratinon, timeout } in msec * @deadline: deadline jiffies for the operation * -* Make sure SStatus of @link reaches stable state, determined by + * Make sure SStatus of @link reaches stable state, determined by * holding the same value where DET is not 1 for @duration polled * every @interval, before @timeout. Timeout constraints the * beginning of the stable state. Because DET gets stuck at 1 on @@ -3760,6 +3758,72 @@ int sata_link_resume(struct ata_link *link, const unsigned long *params, } /** + * sata_link_scr_lpm - manipulate SControl IPM and SPM fields + * @link: ATA link to manipulate SControl for + * @policy: LPM policy to configure + * @spm_wakeup: initiate LPM transition to active state + * + * Manipulate the IPM field of the SControl register of @link + * according to @policy. If @policy is ATA_LPM_MAX_POWER and + * @spm_wakeup is %true, the SPM field is manipulated to wake up + * the link. This function also clears PHYRDY_CHG before + * returning. + * + * LOCKING: + * EH context. + * + * RETURNS: + * 0 on succes, -errno otherwise. + */ +int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy, + bool spm_wakeup) +{ + struct ata_eh_context *ehc = &link->eh_context; + bool woken_up = false; + u32 scontrol; + int rc; + + rc = sata_scr_read(link, SCR_CONTROL, &scontrol); + if (rc) + return rc; + + switch (policy) { + case ATA_LPM_MAX_POWER: + /* disable all LPM transitions */ + scontrol |= (0x3 << 8); + /* initiate transition to active state */ + if (spm_wakeup) { + scontrol |= (0x4 << 12); + woken_up = true; + } + break; + case ATA_LPM_MED_POWER: + /* allow LPM to PARTIAL */ + scontrol &= ~(0x1 << 8); + scontrol |= (0x2 << 8); + break; + case ATA_LPM_MIN_POWER: + /* no restrictions on LPM transitions */ + scontrol &= ~(0x3 << 8); + break; + default: + WARN_ON(1); + } + + rc = sata_scr_write(link, SCR_CONTROL, scontrol); + if (rc) + return rc; + + /* give the link time to transit out of LPM state */ + if (woken_up) + msleep(10); + + /* clear PHYRDY_CHG from SError */ + ehc->i.serror &= ~SERR_PHYRDY_CHG; + return sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG); +} + +/** * ata_std_prereset - prepare for reset * @link: ATA link to be reset * @deadline: deadline jiffies for the operation @@ -4551,6 +4615,7 @@ static unsigned int ata_dev_set_xfermode(struct ata_device *dev) DPRINTK("EXIT, err_mask=%x\n", err_mask); return err_mask; } + /** * ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES * @dev: Device to which command will be sent @@ -4566,8 +4631,7 @@ static unsigned int ata_dev_set_xfermode(struct ata_device *dev) * RETURNS: * 0 on success, AC_ERR_* mask otherwise. */ -static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable, - u8 feature) +unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable, u8 feature) { struct ata_taskfile tf; unsigned int err_mask; @@ -6720,6 +6784,7 @@ EXPORT_SYMBOL_GPL(sata_set_spd); EXPORT_SYMBOL_GPL(ata_wait_after_reset); EXPORT_SYMBOL_GPL(sata_link_debounce); EXPORT_SYMBOL_GPL(sata_link_resume); +EXPORT_SYMBOL_GPL(sata_link_scr_lpm); EXPORT_SYMBOL_GPL(ata_std_prereset); EXPORT_SYMBOL_GPL(sata_link_hardreset); EXPORT_SYMBOL_GPL(sata_std_hardreset); diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h index 1471462..65b6a73 100644 --- a/drivers/ata/libata.h +++ b/drivers/ata/libata.h @@ -86,6 +86,8 @@ extern int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class, extern int ata_dev_configure(struct ata_device *dev); extern int sata_down_spd_limit(struct ata_link *link, u32 spd_limit); extern int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel); +extern unsigned int ata_dev_set_feature(struct ata_device *dev, + u8 enable, u8 feature); extern void ata_sg_clean(struct ata_queued_cmd *qc); extern void ata_qc_free(struct ata_queued_cmd *qc); extern void ata_qc_issue(struct ata_queued_cmd *qc); diff --git a/include/linux/libata.h b/include/linux/libata.h index acfb650..da71bb9 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -950,6 +950,8 @@ extern int sata_link_debounce(struct ata_link *link, const unsigned long *params, unsigned long deadline); extern int sata_link_resume(struct ata_link *link, const unsigned long *params, unsigned long deadline); +extern int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy, + bool spm_wakeup); extern int sata_link_hardreset(struct ata_link *link, const unsigned long *timing, unsigned long deadline, bool *online, int (*check_ready)(struct ata_link *)); -- 1.7.1