From 21f0ba90a447090153edeaf2f14f9f7e8bd9bc80 Mon Sep 17 00:00:00 2001 From: Olaf Rempel Date: Tue, 8 Jun 2010 22:32:38 +0200 Subject: [PATCH] [ARM] orion/kirkwood: reset PCIe unit on boot Patch found in QNAPs vendor source package, with some cleanups (proper defines, shortened max. timeout from 1s to 200ms). Without this patch the PCIe SATA controller (Marvell 88sx7042/sata_mv) in my QNAP TS-419P (Marvell 88f6281/Kirkwood) stops working after a few minutes. The symptomes are described in this thread: http://marc.info/?l=linux-ide&m=124822863706181&w=2 [ Note: this is a workaround in need of a better analysis/solution -- NP ] Acked-by: Saeed Bishara Tested-by: Bernhard R. Link Seconded-by: Martin Michlmayr I'm_not_very_happy_with_it-by: Lennert Buytenhek Signed-off-by: Nicolas Pitre --- arch/arm/plat-orion/pcie.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/arch/arm/plat-orion/pcie.c b/arch/arm/plat-orion/pcie.c index 54c84a4..779553a 100644 --- a/arch/arm/plat-orion/pcie.c +++ b/arch/arm/plat-orion/pcie.c @@ -13,6 +13,7 @@ #include #include #include +#include /* * PCIe unit register offsets. @@ -46,6 +47,8 @@ #define PCIE_STAT_BUS_OFFS 8 #define PCIE_STAT_BUS_MASK 0xff #define PCIE_STAT_LINK_DOWN 1 +#define PCIE_DEBUG_CTRL 0x1a60 +#define PCIE_DEBUG_SOFT_RESET (1<<20) u32 __init orion_pcie_dev_id(void __iomem *base) @@ -85,6 +88,32 @@ void __init orion_pcie_set_local_bus_nr(void __iomem *base, int nr) writel(stat, base + PCIE_STAT_OFF); } +void __init orion_pcie_reset(void __iomem *base) +{ + u32 reg; + int i; + + /* + * MV-S104860-U0, Rev. C: + * PCI Express Unit Soft Reset + * When set, generates an internal reset in the PCI Express unit. + * This bit should be cleared after the link is re-established. + */ + reg = readl(base + PCIE_DEBUG_CTRL); + reg |= PCIE_DEBUG_SOFT_RESET; + writel(reg, base + PCIE_DEBUG_CTRL); + + for (i = 0; i < 20; i++) { + mdelay(10); + + if (orion_pcie_link_up(base)) + break; + } + + reg &= ~(PCIE_DEBUG_SOFT_RESET); + writel(reg, base + PCIE_DEBUG_CTRL); +} + /* * Setup PCIE BARs and Address Decode Wins: * BAR[0,2] -> disabled, BAR[1] -> covers all DRAM banks @@ -153,6 +182,11 @@ void __init orion_pcie_setup(void __iomem *base, u32 mask; /* + * soft reset PCIe unit + */ + orion_pcie_reset(base); + + /* * Point PCIe unit MBUS decode windows to DRAM space. */ orion_pcie_setup_wins(base, dram); -- 2.7.4