Prakash kanthi wrote: > Hi Folks, > > I observed that, even after linux boots and INIT > process starts, rs_timer stays active and causes the > rs_interrupt_single to be called.
Depending on your board and the kernel version you're using, this might be the result of using IRQ 0 for ttyS0 interrupts (as occurs for ppc_405 boards). The stock kernel from kernel.org does not recognize IRQ 0 as a valid value, and sets up rs_timer polling instead. Recent linuxppc_2_4_devel kernels (and perhaps other ppc kernel trees) are modified to remove this restriction; see modifications to drivers/char/serial.c that remove checks for "irq != 0" and such. MontaVista Linux makes this an optional feature, enabled by defining SERIAL_IRQ0_VALID. -- Todd ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
