hw/misc: Add GPIOs for duty in NPCM7xx PWM

This patch adds GPIOs in NPCM7xx PWM module for its duty values.
The purpose of this is to connect it to the MFT module to provide
an input for measuring a PWM fan's RPM. Each PWM module has
NPCM7XX_PWM_PER_MODULE of GPIOs, each one corresponds to
one PWM instance and can connect to multiple fan instances in MFT.

Reviewed-by: Doug Evans <dje@google.com>
Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
Signed-off-by: Hao Wu <wuhaotsh@google.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210311180855.149764-2-wuhaotsh@google.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/misc/npcm7xx_pwm.c b/hw/misc/npcm7xx_pwm.c
index ce192bb27414538c8f7121e5169f3572a86f469b..2be5bd25c6c1750bdf16543800020d8105d2ef1d 100644 (file)
--- a/hw/misc/npcm7xx_pwm.c
+++ b/hw/misc/npcm7xx_pwm.c
@@ -139,6 +139,7 @@ static void npcm7xx_pwm_update_duty(NPCM7xxPWM *p)
         trace_npcm7xx_pwm_update_duty(DEVICE(p->module)->canonical_path,
                                       p->index, p->duty, duty);
         p->duty = duty;
+        qemu_set_irq(p->module->duty_gpio_out[p->index], p->duty);
     }
 }
 
@@ -483,6 +484,7 @@ static void npcm7xx_pwm_init(Object *obj)
     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
     int i;
 
+    QEMU_BUILD_BUG_ON(ARRAY_SIZE(s->pwm) != NPCM7XX_PWM_PER_MODULE);
     for (i = 0; i < NPCM7XX_PWM_PER_MODULE; i++) {
         NPCM7xxPWM *p = &s->pwm[i];
         p->module = s;
@@ -501,6 +503,8 @@ static void npcm7xx_pwm_init(Object *obj)
         object_property_add_uint32_ptr(obj, "duty[*]",
                 &s->pwm[i].duty, OBJ_PROP_FLAG_READ);
     }
+    qdev_init_gpio_out_named(DEVICE(s), s->duty_gpio_out,
+                             "duty-gpio-out", NPCM7XX_PWM_PER_MODULE);
 }
 
 static const VMStateDescription vmstate_npcm7xx_pwm = {

diff --git a/include/hw/misc/npcm7xx_pwm.h b/include/hw/misc/npcm7xx_pwm.h
index 5a689d3f6694b923f2ecf87805fdc74d7917faa8..7ad632a93a1aa386f57e0375107f59f9e055d58e 100644 (file)
--- a/include/hw/misc/npcm7xx_pwm.h
+++ b/include/hw/misc/npcm7xx_pwm.h
@@ -77,6 +77,7 @@ typedef struct NPCM7xxPWM {
  * @iomem: Memory region through which registers are accessed.
  * @clock: The PWM clock.
  * @pwm: The PWM channels owned by this module.
+ * @duty_gpio_out: The duty cycle of each PWM channels as a output GPIO.
  * @ppr: The prescaler register.
  * @csr: The clock selector register.
  * @pcr: The control register.
@@ -89,7 +90,8 @@ struct NPCM7xxPWMState {
     MemoryRegion iomem;
 
     Clock       *clock;
-    NPCM7xxPWM pwm[NPCM7XX_PWM_PER_MODULE];
+    NPCM7xxPWM  pwm[NPCM7XX_PWM_PER_MODULE];
+    qemu_irq    duty_gpio_out[NPCM7XX_PWM_PER_MODULE];
 
     uint32_t    ppr;
     uint32_t    csr;