From 023113d24ef9e1d2b44cb2446872b17e2b01d8b1 Mon Sep 17 00:00:00 2001 From: Xiangliang Yu Date: Thu, 26 Nov 2015 20:27:02 +0800 Subject: [PATCH] AHCI: Fix softreset failed issue of Port Multiplier Current code doesn't update port value of Port Multiplier(PM) when sending FIS of softreset to device, command will fail if FBS is enabled. There are two ways to fix the issue: the first is to disable FBS before sending softreset command to PM device and the second is to update port value of PM when sending command. For the first way, i can't find any related rule in AHCI Spec. The second way can avoid disabling FBS and has better performance. Signed-off-by: Xiangliang Yu Signed-off-by: Tejun Heo Cc: stable@vger.kernel.org --- drivers/ata/libahci.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index 096064cd6c52..4665512dae44 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -1273,6 +1273,15 @@ static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp, ata_tf_to_fis(tf, pmp, is_cmd, fis); ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12)); + /* set port value for softreset of Port Multiplier */ + if (pp->fbs_enabled && pp->fbs_last_dev != pmp) { + tmp = readl(port_mmio + PORT_FBS); + tmp &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC); + tmp |= pmp << PORT_FBS_DEV_OFFSET; + writel(tmp, port_mmio + PORT_FBS); + pp->fbs_last_dev = pmp; + } + /* issue & wait */ writel(1, port_mmio + PORT_CMD_ISSUE);