[PATCH for 2.11 v2 1/2] watchdog: wdt_aspeed: Add support for the reset width register
Andrew Jeffery
andrew at aj.id.au
Wed Aug 9 16:28:26 AEST 2017
The reset width register controls how the pulse on the SoC's WDTRST{1,2}
pins behaves. A pulse is emitted if the external reset bit is set in
WDT_CTRL. On the AST2500 WDT_RESET_WIDTH can consume magic bit patterns
to configure push-pull/open-drain and active-high/active-low
behaviours and thus needs some special handling in the write path.
As some of the capabilities depend on the SoC version a silicon-rev
property is introduced, which is used to guard version-specific
behaviour.
Signed-off-by: Andrew Jeffery <andrew at aj.id.au>
---
hw/watchdog/wdt_aspeed.c | 93 +++++++++++++++++++++++++++++++++++-----
include/hw/watchdog/wdt_aspeed.h | 2 +
2 files changed, 84 insertions(+), 11 deletions(-)
diff --git a/hw/watchdog/wdt_aspeed.c b/hw/watchdog/wdt_aspeed.c
index 8bbe579b6b66..22bce364d7b5 100644
--- a/hw/watchdog/wdt_aspeed.c
+++ b/hw/watchdog/wdt_aspeed.c
@@ -8,16 +8,19 @@
*/
#include "qemu/osdep.h"
+
+#include "qapi/error.h"
#include "qemu/log.h"
+#include "qemu/timer.h"
#include "sysemu/watchdog.h"
+#include "hw/misc/aspeed_scu.h"
#include "hw/sysbus.h"
-#include "qemu/timer.h"
#include "hw/watchdog/wdt_aspeed.h"
-#define WDT_STATUS (0x00 / 4)
-#define WDT_RELOAD_VALUE (0x04 / 4)
-#define WDT_RESTART (0x08 / 4)
-#define WDT_CTRL (0x0C / 4)
+#define WDT_STATUS (0x00 / 4)
+#define WDT_RELOAD_VALUE (0x04 / 4)
+#define WDT_RESTART (0x08 / 4)
+#define WDT_CTRL (0x0C / 4)
#define WDT_CTRL_RESET_MODE_SOC (0x00 << 5)
#define WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5)
#define WDT_CTRL_1MHZ_CLK BIT(4)
@@ -25,18 +28,41 @@
#define WDT_CTRL_WDT_INTR BIT(2)
#define WDT_CTRL_RESET_SYSTEM BIT(1)
#define WDT_CTRL_ENABLE BIT(0)
+#define WDT_RESET_WIDTH (0x18 / 4)
+#define WDT_RESET_WIDTH_ACTIVE_HIGH BIT(31)
+#define WDT_POLARITY_MASK (0xFF << 24)
+#define WDT_ACTIVE_HIGH_MAGIC (0xA5 << 24)
+#define WDT_ACTIVE_LOW_MAGIC (0x5A << 24)
+#define WDT_RESET_WIDTH_PUSH_PULL BIT(30)
+#define WDT_DRIVE_TYPE_MASK (0xFF << 24)
+#define WDT_PUSH_PULL_MAGIC (0xA8 << 24)
+#define WDT_OPEN_DRAIN_MAGIC (0x8A << 24)
-#define WDT_TIMEOUT_STATUS (0x10 / 4)
-#define WDT_TIMEOUT_CLEAR (0x14 / 4)
-#define WDT_RESET_WDITH (0x18 / 4)
+#define WDT_TIMEOUT_STATUS (0x10 / 4)
+#define WDT_TIMEOUT_CLEAR (0x14 / 4)
-#define WDT_RESTART_MAGIC 0x4755
+#define WDT_RESTART_MAGIC 0x4755
static bool aspeed_wdt_is_enabled(const AspeedWDTState *s)
{
return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE;
}
+static bool is_ast2500(const AspeedWDTState *s)
+{
+ switch (s->silicon_rev) {
+ case AST2500_A0_SILICON_REV:
+ case AST2500_A1_SILICON_REV:
+ return true;
+ case AST2400_A0_SILICON_REV:
+ case AST2400_A1_SILICON_REV:
+ default:
+ break;
+ }
+
+ return false;
+}
+
static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size)
{
AspeedWDTState *s = ASPEED_WDT(opaque);
@@ -55,9 +81,10 @@ static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size)
return 0;
case WDT_CTRL:
return s->regs[WDT_CTRL];
+ case WDT_RESET_WIDTH:
+ return s->regs[WDT_RESET_WIDTH];
case WDT_TIMEOUT_STATUS:
case WDT_TIMEOUT_CLEAR:
- case WDT_RESET_WDITH:
qemu_log_mask(LOG_UNIMP,
"%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n",
__func__, offset);
@@ -119,9 +146,27 @@ static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data,
timer_del(s->timer);
}
break;
+ case WDT_RESET_WIDTH:
+ {
+ uint32_t property = data & WDT_POLARITY_MASK;
+
+ if (property && is_ast2500(s)) {
+ if (property == WDT_ACTIVE_HIGH_MAGIC) {
+ s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH;
+ } else if (property == WDT_ACTIVE_LOW_MAGIC) {
+ s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH;
+ } else if (property == WDT_PUSH_PULL_MAGIC) {
+ s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL;
+ } else if (property == WDT_OPEN_DRAIN_MAGIC) {
+ s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL;
+ }
+ }
+ s->regs[WDT_RESET_WIDTH] &= ~s->ext_pulse_width_mask;
+ s->regs[WDT_RESET_WIDTH] |= data & s->ext_pulse_width_mask;
+ break;
+ }
case WDT_TIMEOUT_STATUS:
case WDT_TIMEOUT_CLEAR:
- case WDT_RESET_WDITH:
qemu_log_mask(LOG_UNIMP,
"%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n",
__func__, offset);
@@ -167,6 +212,7 @@ static void aspeed_wdt_reset(DeviceState *dev)
s->regs[WDT_RELOAD_VALUE] = 0x03EF1480;
s->regs[WDT_RESTART] = 0;
s->regs[WDT_CTRL] = 0;
+ s->regs[WDT_RESET_WIDTH] = 0xFF;
timer_del(s->timer);
}
@@ -187,6 +233,25 @@ static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
AspeedWDTState *s = ASPEED_WDT(dev);
+ if (!is_supported_silicon_rev(s->silicon_rev)) {
+ error_setg(errp, "Unknown silicon revision: 0x%" PRIx32,
+ s->silicon_rev);
+ return;
+ }
+
+ switch (s->silicon_rev) {
+ case AST2400_A0_SILICON_REV:
+ case AST2400_A1_SILICON_REV:
+ s->ext_pulse_width_mask = 0xff;
+ break;
+ case AST2500_A0_SILICON_REV:
+ case AST2500_A1_SILICON_REV:
+ s->ext_pulse_width_mask = 0xfffff;
+ break;
+ default:
+ g_assert_not_reached();
+ }
+
s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev);
/* FIXME: This setting should be derived from the SCU hw strapping
@@ -199,6 +264,11 @@ static void aspeed_wdt_realize(DeviceState *dev, Error **errp)
sysbus_init_mmio(sbd, &s->iomem);
}
+static Property aspeed_wdt_properties[] = {
+ DEFINE_PROP_UINT32("silicon-rev", AspeedWDTState, silicon_rev, 0),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
static void aspeed_wdt_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
@@ -207,6 +277,7 @@ static void aspeed_wdt_class_init(ObjectClass *klass, void *data)
dc->reset = aspeed_wdt_reset;
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
dc->vmsd = &vmstate_aspeed_wdt;
+ dc->props = aspeed_wdt_properties;
}
static const TypeInfo aspeed_wdt_info = {
diff --git a/include/hw/watchdog/wdt_aspeed.h b/include/hw/watchdog/wdt_aspeed.h
index 080c2231222e..7de3e5c224fb 100644
--- a/include/hw/watchdog/wdt_aspeed.h
+++ b/include/hw/watchdog/wdt_aspeed.h
@@ -27,6 +27,8 @@ typedef struct AspeedWDTState {
uint32_t regs[ASPEED_WDT_REGS_MAX];
uint32_t pclk_freq;
+ uint32_t silicon_rev;
+ uint32_t ext_pulse_width_mask;
} AspeedWDTState;
#endif /* ASPEED_WDT_H */
--
2.11.0
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