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authorBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>2020-03-26 18:58:13 +0300
committerJens Axboe <axboe@kernel.dk>2020-03-26 19:28:19 +0300
commitab4117cf2470618ffd5af16fa7c363b81260d6e7 (patch)
tree75cd385617b052edad3837135b6ab6523c9a8d5f /drivers/ata/libata-sata.c
parent6eab1bc0eecb541f4c383a0823902dc8f5d99861 (diff)
downloadlinux-ab4117cf2470618ffd5af16fa7c363b81260d6e7.tar.xz
ata: move *sata_set_spd*() to libata-sata.c
* move *sata_set_spd*() to libata-sata.c * add static inlines for CONFIG_SATA_HOST=n case Code size savings on m68k arch using (modified) atari_defconfig: text data bss dec hex filename before: 32842 572 40 33458 82ae drivers/ata/libata-core.o after: 32812 572 40 33428 8290 drivers/ata/libata-core.o Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/ata/libata-sata.c')
-rw-r--r--drivers/ata/libata-sata.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 1ef4c19864ac..d66afdc33d54 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -271,6 +271,87 @@ int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
}
EXPORT_SYMBOL_GPL(sata_link_scr_lpm);
+static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
+{
+ struct ata_link *host_link = &link->ap->link;
+ u32 limit, target, spd;
+
+ limit = link->sata_spd_limit;
+
+ /* Don't configure downstream link faster than upstream link.
+ * It doesn't speed up anything and some PMPs choke on such
+ * configuration.
+ */
+ if (!ata_is_host_link(link) && host_link->sata_spd)
+ limit &= (1 << host_link->sata_spd) - 1;
+
+ if (limit == UINT_MAX)
+ target = 0;
+ else
+ target = fls(limit);
+
+ spd = (*scontrol >> 4) & 0xf;
+ *scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
+
+ return spd != target;
+}
+
+/**
+ * sata_set_spd_needed - is SATA spd configuration needed
+ * @link: Link in question
+ *
+ * Test whether the spd limit in SControl matches
+ * @link->sata_spd_limit. This function is used to determine
+ * whether hardreset is necessary to apply SATA spd
+ * configuration.
+ *
+ * LOCKING:
+ * Inherited from caller.
+ *
+ * RETURNS:
+ * 1 if SATA spd configuration is needed, 0 otherwise.
+ */
+int sata_set_spd_needed(struct ata_link *link)
+{
+ u32 scontrol;
+
+ if (sata_scr_read(link, SCR_CONTROL, &scontrol))
+ return 1;
+
+ return __sata_set_spd_needed(link, &scontrol);
+}
+
+/**
+ * sata_set_spd - set SATA spd according to spd limit
+ * @link: Link to set SATA spd for
+ *
+ * Set SATA spd of @link according to sata_spd_limit.
+ *
+ * LOCKING:
+ * Inherited from caller.
+ *
+ * RETURNS:
+ * 0 if spd doesn't need to be changed, 1 if spd has been
+ * changed. Negative errno if SCR registers are inaccessible.
+ */
+int sata_set_spd(struct ata_link *link)
+{
+ u32 scontrol;
+ int rc;
+
+ if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
+ return rc;
+
+ if (!__sata_set_spd_needed(link, &scontrol))
+ return 0;
+
+ if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
+ return rc;
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(sata_set_spd);
+
/**
* ata_slave_link_init - initialize slave link
* @ap: port to initialize slave link for