On Tue, 3 Jun 2014 00:10:17 -0700 Antoine Ténart <antoine.tenart@xxxxxxxxxxxxxxxxxx> wrote: > Hi Jisheng, > > On Tue, Jun 03, 2014 at 02:31:13PM +0800, Jisheng Zhang wrote: > > On Mon, 2 Jun 2014 02:21:02 -0700 > > Antoine Ténart <antoine.tenart@xxxxxxxxxxxxxxxxxx> wrote: > > > + > > > +extern void berlin_secondary_startup(void); > > > +extern u32 boot_inst; > > > + > > > +static void __iomem *cpu_ctrl; > > > + > > > +static inline void berlin_reset_cpu(unsigned int cpu) > > > +{ > > > + u32 val; > > > + > > > + val = readl(cpu_ctrl + CPU_RESET); > > > + val |= BIT(cpu_logical_map(cpu)); > > > + writel(val, cpu_ctrl + CPU_RESET); > > > > "writel(BIT(cpu_logical_map(cpu)), cpu_ctrl + CPU_RESET)" is enough. > > we don't need to read and modify, because we writing 0 has no any effect. > > The reset bit is automatically cleared but I dumped the register value > and it wasn't 0x0, that's why I preferred to read first and only set the > reset bit. > > > > + > > > + /* > > > + * Write the first instruction the CPU will execute after being > > > reseted > > > + * in the reset exception register. > > > + */ > > > + writel(boot_inst, vectors_base + RESET_VECT); > > > > Is it better to let bootloader/firmware handle this writing. Then, we can > > also remove the tricky boot_inst in headsmp.S. > > We thought about it, and since it can be difficult to update the > bootloader for some boards, like BG2 based ones, we preferred to include > this here. > > Thanks! > > Antoine > Got your points. Thanks very much -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html