zynq_slcr_cpu_start/stop() ignored the current register state when writing to a register. Fixing this by implementing proper read-modify-write.
Signed-off-by: Soren Brinkmann <[email protected]> --- arch/arm/mach-zynq/slcr.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/arm/mach-zynq/slcr.c b/arch/arm/mach-zynq/slcr.c index 44a4ab6..1836d5a 100644 --- a/arch/arm/mach-zynq/slcr.c +++ b/arch/arm/mach-zynq/slcr.c @@ -61,11 +61,11 @@ void zynq_slcr_system_reset(void) */ void zynq_slcr_cpu_start(int cpu) { - /* enable CPUn */ - writel(SLCR_A9_CPU_CLKSTOP << cpu, - zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); - /* enable CLK for CPUn */ - writel(0x0 << cpu, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); + u32 reg = readl(zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); + reg &= ~(SLCR_A9_CPU_RST << cpu); + writel(reg, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); + reg &= ~(SLCR_A9_CPU_CLKSTOP << cpu); + writel(reg, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); } /** @@ -74,9 +74,9 @@ void zynq_slcr_cpu_start(int cpu) */ void zynq_slcr_cpu_stop(int cpu) { - /* stop CLK and reset CPUn */ - writel((SLCR_A9_CPU_CLKSTOP | SLCR_A9_CPU_RST) << cpu, - zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); + u32 reg = readl(zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); + reg |= (SLCR_A9_CPU_CLKSTOP | SLCR_A9_CPU_RST) << cpu; + writel(reg, zynq_slcr_base + SLCR_A9_CPU_RST_CTRL_OFFSET); } /** -- 1.8.3.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
