diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c index 37501fd0973d..f03aab187f4d 100644 --- a/drivers/ata/ahci_xgene.c +++ b/drivers/ata/ahci_xgene.c @@ -78,6 +78,9 @@ #define CFG_MEM_RAM_SHUTDOWN 0x00000070 #define BLOCK_MEM_RDY 0x00000074 +/* Max retry for link down */ +#define MAX_LINK_DOWN_RETRY 3 + struct xgene_ahci_context { struct ahci_host_priv *hpriv; struct device *dev; @@ -237,8 +240,11 @@ static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel) * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will * report disparity error and etc. In addition, during COMRESET, there can * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and - * SERR_10B_8B_ERR, the PHY receiver line must be reseted. The following - * algorithm is followed to proper configure the hardware PHY during COMRESET: + * SERR_10B_8B_ERR, the PHY receiver line must be reseted. Also during long + * reboot cycle regression, sometimes the PHY reports link down even if the + * device is present because of speed negotiation failure. so need to retry + * the COMRESET to get the link up. The following algorithm is followed to + * proper configure the hardware PHY during COMRESET: * * Alg Part 1: * 1. Start the PHY at Gen3 speed (default setting) @@ -254,9 +260,15 @@ static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel) * Alg Part 2: * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error * reported in the register PORT_SCR_ERR, then reset the PHY receiver line - * 2. Go to Alg Part 3 + * 2. Go to Alg Part 4 * * Alg Part 3: + * 1. Check the PORT_SCR_STAT to see whether device presence detected but PHY + * communication establishment failed and maximum link down attempts are + * less than Max attempts 3 then goto Alg Part 1. + * 2. Go to Alg Part 4. + * + * Alg Part 4: * 1. Clear any pending from register PORT_SCR_ERR. * * NOTE: For the initial version, we will NOT support Gen1/Gen2. In addition @@ -275,19 +287,27 @@ static int xgene_ahci_do_hardreset(struct ata_link *link, u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG; void __iomem *port_mmio = ahci_port_base(ap); struct ata_taskfile tf; + int link_down_retry = 0; int rc; - u32 val; + u32 val, sstatus; - /* clear D2H reception area to properly wait for D2H FIS */ - ata_tf_init(link->device, &tf); - tf.command = ATA_BUSY; - ata_tf_to_fis(&tf, 0, 0, d2h_fis); - rc = sata_link_hardreset(link, timing, deadline, online, + do { + /* clear D2H reception area to properly wait for D2H FIS */ + ata_tf_init(link->device, &tf); + tf.command = ATA_BUSY; + ata_tf_to_fis(&tf, 0, 0, d2h_fis); + rc = sata_link_hardreset(link, timing, deadline, online, ahci_check_ready); + if (*online) { + val = readl(port_mmio + PORT_SCR_ERR); + if (val & (SERR_DISPARITY | SERR_10B_8B_ERR)) + dev_warn(ctx->dev, "link has error\n"); + break; + } - val = readl(port_mmio + PORT_SCR_ERR); - if (val & (SERR_DISPARITY | SERR_10B_8B_ERR)) - dev_warn(ctx->dev, "link has error\n"); + sata_scr_read(link, SCR_STATUS, &sstatus); + } while (link_down_retry++ < MAX_LINK_DOWN_RETRY && + (sstatus & 0xff) == 0x1); /* clear all errors if any pending */ val = readl(port_mmio + PORT_SCR_ERR);