sata_sil24: implement PORT_RST

As DEV_RST (hardreset) sometimes fail to recover the controller
(especially after PMP DMA CS errata).  In such cases, perform PORT_RST
prior to DEV_RST.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 70 insertions, 23 deletions

diff --git a/drivers/ata/sata_sil24.c b/drivers/ata/sata_sil24.c
index 03bfbb65c533..15b9a80a1782 100644
--- a/drivers/ata/sata_sil24.c
+++ b/drivers/ata/sata_sil24.c
@@ -323,6 +323,7 @@ struct sil24_port_priv {
         union sil24_cmd_block *cmd_block;       /* 32 cmd blocks */
         dma_addr_t cmd_block_dma;               /* DMA base addr for them */
         struct ata_taskfile tf;                 /* Cached taskfile registers */
+        int do_port_rst;
 };
 
 static void sil24_dev_config(struct ata_device *dev);
@@ -536,6 +537,31 @@ static void sil24_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
         *tf = pp->tf;
 }
 
+static void sil24_config_port(struct ata_port *ap)
+{
+        void __iomem *port = ap->ioaddr.cmd_addr;
+
+        /* configure IRQ WoC */
+        if (ap->flags & SIL24_FLAG_PCIX_IRQ_WOC)
+                writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_STAT);
+        else
+                writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_CLR);
+
+        /* zero error counters. */
+        writel(0x8000, port + PORT_DECODE_ERR_THRESH);
+        writel(0x8000, port + PORT_CRC_ERR_THRESH);
+        writel(0x8000, port + PORT_HSHK_ERR_THRESH);
+        writel(0x0000, port + PORT_DECODE_ERR_CNT);
+        writel(0x0000, port + PORT_CRC_ERR_CNT);
+        writel(0x0000, port + PORT_HSHK_ERR_CNT);
+
+        /* always use 64bit activation */
+        writel(PORT_CS_32BIT_ACTV, port + PORT_CTRL_CLR);
+
+        /* clear port multiplier enable and resume bits */
+        writel(PORT_CS_PMP_EN | PORT_CS_PMP_RESUME, port + PORT_CTRL_CLR);
+}
+
 static void sil24_config_pmp(struct ata_port *ap, int attached)
 {
         void __iomem *port = ap->ioaddr.cmd_addr;
@@ -564,6 +590,7 @@ static void sil24_clear_pmp(struct ata_port *ap)
 static int sil24_init_port(struct ata_port *ap)
 {
         void __iomem *port = ap->ioaddr.cmd_addr;
+        struct sil24_port_priv *pp = ap->private_data;
         u32 tmp;
 
         /* clear PMP error status */
@@ -576,8 +603,12 @@ static int sil24_init_port(struct ata_port *ap)
         tmp = ata_wait_register(port + PORT_CTRL_STAT,
                                 PORT_CS_RDY, 0, 10, 100);
 
-        if ((tmp & (PORT_CS_INIT | PORT_CS_RDY)) != PORT_CS_RDY)
+        if ((tmp & (PORT_CS_INIT | PORT_CS_RDY)) != PORT_CS_RDY) {
+                pp->do_port_rst = 1;
+                ap->link.eh_context.i.action |= ATA_EH_HARDRESET;
                 return -EIO;
+        }
+
         return 0;
 }
 
@@ -692,10 +723,34 @@ static int sil24_hardreset(struct ata_link *link, unsigned int *class,
 {
         struct ata_port *ap = link->ap;
         void __iomem *port = ap->ioaddr.cmd_addr;
+        struct sil24_port_priv *pp = ap->private_data;
+        int did_port_rst = 0;
         const char *reason;
         int tout_msec, rc;
         u32 tmp;
 
+ retry:
+        /* Sometimes, DEV_RST is not enough to recover the controller.
+         * This happens often after PM DMA CS errata.
+         */
+        if (pp->do_port_rst) {
+                ata_port_printk(ap, KERN_WARNING, "controller in dubious "
+                                "state, performing PORT_RST\n");
+
+                writel(PORT_CS_PORT_RST, port + PORT_CTRL_STAT);
+                msleep(10);
+                writel(PORT_CS_PORT_RST, port + PORT_CTRL_CLR);
+                ata_wait_register(port + PORT_CTRL_STAT, PORT_CS_RDY, 0,
+                                  10, 5000);
+
+                /* restore port configuration */
+                sil24_config_port(ap);
+                sil24_config_pmp(ap, ap->nr_pmp_links);
+
+                pp->do_port_rst = 0;
+                did_port_rst = 1;
+        }
+
         /* sil24 does the right thing(tm) without any protection */
         sata_set_spd(link);
 
@@ -732,6 +787,11 @@ static int sil24_hardreset(struct ata_link *link, unsigned int *class,
         return -EAGAIN;
 
  err:
+        if (!did_port_rst) {
+                pp->do_port_rst = 1;
+                goto retry;
+        }
+
         ata_link_printk(link, KERN_ERR, "hardreset failed (%s)\n", reason);
         return -EIO;
 }
@@ -997,6 +1057,7 @@ static void sil24_error_intr(struct ata_port *ap)
                         ehi->err_mask |= AC_ERR_OTHER;
                         ehi->action |= ATA_EH_HARDRESET;
                         ata_ehi_push_desc(ehi, "PMP DMA CS errata");
+                        pp->do_port_rst = 1;
                         freeze = 1;
                 }
 
@@ -1152,6 +1213,8 @@ static irqreturn_t sil24_interrupt(int irq, void *dev_instance)
 
 static void sil24_error_handler(struct ata_port *ap)
 {
+        struct sil24_port_priv *pp = ap->private_data;
+
         if (sil24_init_port(ap))
                 ata_eh_freeze_port(ap);
 
@@ -1160,6 +1223,8 @@ static void sil24_error_handler(struct ata_port *ap)
                        ata_std_postreset, sata_pmp_std_prereset,
                        sil24_pmp_softreset, sil24_pmp_hardreset,
                        sata_pmp_std_postreset);
+
+        pp->do_port_rst = 0;
 }
 
 static void sil24_post_internal_cmd(struct ata_queued_cmd *qc)
@@ -1206,7 +1271,6 @@ static int sil24_port_start(struct ata_port *ap)
 static void sil24_init_controller(struct ata_host *host)
 {
         void __iomem *host_base = host->iomap[SIL24_HOST_BAR];
-        void __iomem *port_base = host->iomap[SIL24_PORT_BAR];
         u32 tmp;
         int i;
 
@@ -1218,7 +1282,8 @@ static void sil24_init_controller(struct ata_host *host)
 
         /* init ports */
         for (i = 0; i < host->n_ports; i++) {
-                void __iomem *port = port_base + i * PORT_REGS_SIZE;
+                struct ata_port *ap = host->ports[i];
+                void __iomem *port = ap->ioaddr.cmd_addr;
 
                 /* Initial PHY setting */
                 writel(0x20c, port + PORT_PHY_CFG);
@@ -1235,26 +1300,8 @@ static void sil24_init_controller(struct ata_host *host)
                                            "failed to clear port RST\n");
                 }
 
-                /* Configure IRQ WoC */
-                if (host->ports[0]->flags & SIL24_FLAG_PCIX_IRQ_WOC)
-                        writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_STAT);
-                else
-                        writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_CLR);
-
-                /* Zero error counters. */
-                writel(0x8000, port + PORT_DECODE_ERR_THRESH);
-                writel(0x8000, port + PORT_CRC_ERR_THRESH);
-                writel(0x8000, port + PORT_HSHK_ERR_THRESH);
-                writel(0x0000, port + PORT_DECODE_ERR_CNT);
-                writel(0x0000, port + PORT_CRC_ERR_CNT);
-                writel(0x0000, port + PORT_HSHK_ERR_CNT);
-
-                /* Always use 64bit activation */
-                writel(PORT_CS_32BIT_ACTV, port + PORT_CTRL_CLR);
-
-                /* Clear port multiplier enable and resume bits */
-                writel(PORT_CS_PMP_EN | PORT_CS_PMP_RESUME,
-                       port + PORT_CTRL_CLR);
+                /* configure port */
+                sil24_config_port(ap);
         }
 
         /* Turn on interrupts */