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2020-10-20hw/timer/bcm2835: Support the timer COMPARE registersPhilippe Mathieu-Daudé1-17/+31
This peripheral has 1 free-running timer and 4 compare registers. Only the free-running timer is implemented. Add support the COMPARE registers (each register is wired to an IRQ). Reference: "BCM2835 ARM Peripherals" datasheet [*] chapter 12 "System Timer": The System Timer peripheral provides four 32-bit timer channels and a single 64-bit free running counter. Each channel has an output compare register, which is compared against the 32 least significant bits of the free running counter values. When the two values match, the system timer peripheral generates a signal to indicate a match for the appropriate channel. The match signal is then fed into the interrupt controller. This peripheral is used since Linux 3.7, commit ee4af5696720 ("ARM: bcm2835: add system timer"). [*] https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Luc Michel <luc@lmichel.fr> Message-id: 20201010203709.3116542-4-f4bug@amsat.org Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-10-20hw/timer/bcm2835: Rename variable holding CTRL_STATUS registerPhilippe Mathieu-Daudé1-4/+4
The variable holding the CTRL_STATUS register is misnamed 'status'. Rename it 'ctrl_status' to make it more obvious this register is also used to control the peripheral. Reviewed-by: Luc Michel <luc.michel@greensocs.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20201010203709.3116542-3-f4bug@amsat.org Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-10-20hw/timer/bcm2835: Introduce BCM2835_SYSTIMER_COUNT definitionPhilippe Mathieu-Daudé1-1/+2
Use the BCM2835_SYSTIMER_COUNT definition instead of the magic '4' value. Reviewed-by: Luc Michel <luc.michel@greensocs.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20201010203709.3116542-2-f4bug@amsat.org Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-10-25hw/timer/bcm2835: Add the BCM2835 SYS_timerPhilippe Mathieu-Daudé1-0/+163
Add the 64-bit free running timer. Do not model the COMPARE register (no IRQ generated). This timer is used by Linux kernel and recently U-Boot: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clocksource/bcm2835_timer.c?h=v3.7 https://github.com/u-boot/u-boot/blob/v2019.07/include/configs/rpi.h#L19 Datasheet used: https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-id: 20191019234715.25750-4-f4bug@amsat.org [PMM: squashed in switch to using memset in reset] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>