These are some of the messages coming on console from Microzed board (Cortex A9):[Sat May 17 18:18:26.603 2014] DMA: preallocated 256 KiB pool for atomic coherent allocations[Sat May 17 18:18:26.603 2014] xgpiops e000a000.ps7-gpio: gpio at 0xe000a000 mapped to 0xf004e000[Sat May 17 18:18:26.603 2014] usbcore: registered new interface driver usbfs[Sat May 17 18:18:26.624 2014] usbcore: registered new interface driver hub[Sat May 17 18:18:26.624 2014] usbcore: registered new device driver usb[Sat May 17 18:18:26.624 2014] Switching to clocksource xttcps_clocksource[Sat May 17 18:18:26.624 2014] e0001000.serial: ttyPS0 at MMIO 0xe0001000 (irq = 82) is a xuartps[Sat May 17 18:18:26.624 2014] console [ttyPS0] enabled[Sat May 17 18:18:26.634 2014] xdevcfg f8007000.ps7-dev-cfg: ioremap f8007000 to f0052000 with size 100[Sat May 17 18:18:26.662 2014] xqspips e000d000.ps7-qspi: master is unqueued, this is deprecated[Sat May 17 18:18:26.662 2014] spi spi32766.0: setup: unsupported mode bits 3[Sat May 17 18:18:26.662 2014] xqspips e000d000.ps7-qspi: can't setup spi32766.0, status -22[Sat May 17 18:18:26.662 2014] spi_master spi32766: spi_device register error /amba@0/ps7-qspi@e000d000/ps7-qspi@0[Sat May 17 18:18:26.662 2014] xqspips e000d000.ps7-qspi: at 0xE000D000 mapped to 0xF0054000, irq=51[Sat May 17 18:18:26.671 2014] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver[Sat May 17 18:18:26.680 2014] ULPI transceiver vendor/product ID 0x0424/0x0007After the line:[Sat May 17 18:18:26.624 2014] usbcore: registered new device driver usbI want to check that the USB driver is indeed loaded. One way I thought to see this would be to light an LED immediately after this line is printed on the console.But how do I do this? Is there any other better way of doing this?My main requirement is to measure the timing right from power ON until the USB driver is loaded. This can be done if I get any signal on the board the moment USB driver is loaded. I will capture this signal along with power ON, and this will give me precise information about the time USB is loaded.This precision cannot be achieved by looking at the time stamps in log file since the messages do not come immediately and there is considerable time spent before the message start coming.
Sending signal to user that a particular driver is loaded
linux;startup;drivers