socfpga: hotplug: put cpu1 in wfi
Use WFI when putting CPU1 to sleep. Don't hold CPU1 in reset
since that results in increased power consumption.
Reset CPU1 briefly during CPU1 bootup.
This has been tested for hotplug and suspend/resume and results
in no increased power consumption.
Signed-off-by: Alan Tull <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Signed-off-by: Dinh Nguyen <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c
index 16ca97b..c64d89b 100644
--- a/arch/arm/mach-socfpga/platsmp.c
+++ b/arch/arm/mach-socfpga/platsmp.c
@@ -34,17 +34,21 @@
int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
if (socfpga_cpu1start_addr) {
+ /* This will put CPU #1 into reset. */
+ writel(RSTMGR_MPUMODRST_CPU1,
+ rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
+
memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
- __raw_writel(virt_to_phys(socfpga_secondary_startup),
- (sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff)));
+ writel(virt_to_phys(socfpga_secondary_startup),
+ sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));
flush_cache_all();
smp_wmb();
outer_clean_range(0, trampoline_size);
- /* This will release CPU #1 out of reset.*/
- __raw_writel(0, rst_manager_base_addr + 0x10);
+ /* This will release CPU #1 out of reset. */
+ writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
}
return 0;
@@ -86,10 +90,9 @@
*/
static void socfpga_cpu_die(unsigned int cpu)
{
- cpu_do_idle();
-
- /* We should have never returned from idle */
- panic("cpu %d unexpectedly exit from shutdown\n", cpu);
+ /* Do WFI. If we wake up early, go back into WFI */
+ while (1)
+ cpu_do_idle();
}
struct smp_operations socfpga_smp_ops __initdata = {