From b989b89f672597cc0e780b5ce95e604d4f49247a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Tue, 23 Jun 2020 09:27:20 +0200 Subject: hw/misc/pca9552: Trace GPIO High/Low events MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a trivial representation of the PCA9552 GPIOs. Example booting obmc-phosphor-image: $ qemu-system-arm -M witherspoon-bmc -trace pca955x_gpio_status 1592689902.327837:pca955x_gpio_status pca-unspecified GPIOs 0-15 [*...............] 1592689902.329934:pca955x_gpio_status pca-unspecified GPIOs 0-15 [**..............] 1592689902.330717:pca955x_gpio_status pca-unspecified GPIOs 0-15 [***.............] 1592689902.331431:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****............] 1592689902.332163:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*..] 1592689902.332888:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........**.] 1592689902.333629:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........***] 1592690032.793289:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*] 1592690033.303163:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........***] 1592690033.812962:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*] 1592690034.323234:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........***] 1592690034.832922:pca955x_gpio_status pca-unspecified GPIOs 0-15 [****.........*.*] We notice the GPIO #14 (front-power LED) starts to blink. This LED is described in the witherspoon device-tree [*]: front-power { retain-state-shutdown; default-state = "keep"; gpios = <&pca0 14 GPIO_ACTIVE_LOW>; }; [*] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts?id=b1f9be9392f0#n140 Suggested-by: Cédric Le Goater Reviewed-by: Cédric Le Goater Signed-off-by: Philippe Mathieu-Daudé Tested-by: Cédric Le Goater Message-id: 20200623072723.6324-7-f4bug@amsat.org Signed-off-by: Peter Maydell --- hw/misc/pca9552.c | 39 +++++++++++++++++++++++++++++++++++++++ hw/misc/trace-events | 3 +++ 2 files changed, 42 insertions(+) diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c index 2cc52b0..41f8ad2 100644 --- a/hw/misc/pca9552.c +++ b/hw/misc/pca9552.c @@ -13,12 +13,14 @@ #include "qemu/osdep.h" #include "qemu/log.h" #include "qemu/module.h" +#include "qemu/bitops.h" #include "hw/qdev-properties.h" #include "hw/misc/pca9552.h" #include "hw/misc/pca9552_regs.h" #include "migration/vmstate.h" #include "qapi/error.h" #include "qapi/visitor.h" +#include "trace.h" typedef struct PCA955xClass { /*< private >*/ @@ -49,6 +51,39 @@ static uint8_t pca955x_pin_get_config(PCA955xState *s, int pin) return extract32(s->regs[reg], shift, 2); } +/* Return INPUT status (bit #N belongs to GPIO #N) */ +static uint16_t pca955x_pins_get_status(PCA955xState *s) +{ + return (s->regs[PCA9552_INPUT1] << 8) | s->regs[PCA9552_INPUT0]; +} + +static void pca955x_display_pins_status(PCA955xState *s, + uint16_t previous_pins_status) +{ + PCA955xClass *k = PCA955X_GET_CLASS(s); + uint16_t pins_status, pins_changed; + int i; + + pins_status = pca955x_pins_get_status(s); + pins_changed = previous_pins_status ^ pins_status; + if (!pins_changed) { + return; + } + if (trace_event_get_state_backends(TRACE_PCA955X_GPIO_STATUS)) { + char *buf = g_newa(char, k->pin_count + 1); + + for (i = 0; i < k->pin_count; i++) { + if (extract32(pins_status, i, 1)) { + buf[i] = '*'; + } else { + buf[i] = '.'; + } + } + buf[i] = '\0'; + trace_pca955x_gpio_status(s->description, buf); + } +} + static void pca955x_update_pin_input(PCA955xState *s) { PCA955xClass *k = PCA955X_GET_CLASS(s); @@ -98,6 +133,8 @@ static uint8_t pca955x_read(PCA955xState *s, uint8_t reg) static void pca955x_write(PCA955xState *s, uint8_t reg, uint8_t data) { + uint16_t pins_status; + switch (reg) { case PCA9552_PSC0: case PCA9552_PWM0: @@ -110,8 +147,10 @@ static void pca955x_write(PCA955xState *s, uint8_t reg, uint8_t data) case PCA9552_LS1: case PCA9552_LS2: case PCA9552_LS3: + pins_status = pca955x_pins_get_status(s); s->regs[reg] = data; pca955x_update_pin_input(s); + pca955x_display_pins_status(s, pins_status); break; case PCA9552_INPUT0: diff --git a/hw/misc/trace-events b/hw/misc/trace-events index 68a6d9f..bd7bd37 100644 --- a/hw/misc/trace-events +++ b/hw/misc/trace-events @@ -209,3 +209,6 @@ via1_adb_poll(uint8_t data, const char *vadbint, int status, int index, int size # grlib_ahb_apb_pnp.c grlib_ahb_pnp_read(uint64_t addr, uint32_t value) "AHB PnP read addr:0x%03"PRIx64" data:0x%08x" grlib_apb_pnp_read(uint64_t addr, uint32_t value) "APB PnP read addr:0x%03"PRIx64" data:0x%08x" + +# pca9552.c +pca955x_gpio_status(const char *description, const char *buf) "%s GPIOs 0-15 [%s]" -- cgit v1.1