From 985af6f70dbb8a33b3af8a7c7df508d924650e37 Mon Sep 17 00:00:00 2001 From: Marcin Tomczak Date: Fri, 29 Jul 2011 17:16:50 -0700 Subject: [SCSI] isci: change sas phy timeouts from 54us to 59us Need the following workaround in the driver for interoperability with the older Intel SSD drives and any other SATA drive that may exhibit the same behavior. This is a corner case where SCU speed is limited to either 3G or 1.5G and the drive has a period of DC idle when it switches speed during SATA speed negotiation. Workaround :change PHYTOV[31:24] from 0x36 to 0x3B. Signed-off-by: Marcin Tomczak Signed-off-by: Dan Williams Signed-off-by: James Bottomley --- drivers/scsi/isci/phy.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/scsi/isci/phy.c') diff --git a/drivers/scsi/isci/phy.c b/drivers/scsi/isci/phy.c index 79313a7a2356..430fc8ff014a 100644 --- a/drivers/scsi/isci/phy.c +++ b/drivers/scsi/isci/phy.c @@ -104,6 +104,7 @@ sci_phy_link_layer_initialization(struct isci_phy *iphy, u32 parity_count = 0; u32 llctl, link_rate; u32 clksm_value = 0; + u32 sp_timeouts = 0; iphy->link_layer_registers = reg; @@ -211,6 +212,18 @@ sci_phy_link_layer_initialization(struct isci_phy *iphy, llctl |= SCU_SAS_LLCTL_GEN_VAL(MAX_LINK_RATE, link_rate); writel(llctl, &iphy->link_layer_registers->link_layer_control); + sp_timeouts = readl(&iphy->link_layer_registers->sas_phy_timeouts); + + /* Clear the default 0x36 (54us) RATE_CHANGE timeout value. */ + sp_timeouts &= ~SCU_SAS_PHYTOV_GEN_VAL(RATE_CHANGE, 0xFF); + + /* Set RATE_CHANGE timeout value to 0x3B (59us). This ensures SCU can + * lock with 3Gb drive when SCU max rate is set to 1.5Gb. + */ + sp_timeouts |= SCU_SAS_PHYTOV_GEN_VAL(RATE_CHANGE, 0x3B); + + writel(sp_timeouts, &iphy->link_layer_registers->sas_phy_timeouts); + if (is_a2(ihost->pdev)) { /* Program the max ARB time for the PHY to 700us so we inter-operate with * the PMC expander which shuts down PHYs if the expander PHY generates too -- cgit v1.2.3