New subject: [PATCH 2/3] target-i386: reserve RCRB mmio space in ACPI DSDT table

27 May 2015

This interface provides some registers within a 32-byte range and can be
acessed through PCI-to-LPC bridge interface (PMBASE + 0x60).

It's commonly used as a watchdog timer to detect system lockups through
SMIs that are generated -- if TCO_EN bit is set -- on every timeout. If
NO_REBOOT bit is not set in GCS (General Control and Status register),
the system will be resetted upon second timeout if TCO_RLD register
wasn't previously written to prevent timeout.

This patch adds support to TCO watchdog logic and few other features
like mapping NMIs to SMIs (NMI2SMI_EN bit), system intruder detection,
etc. are not implemented yet.

Signed-off-by: Paulo Alcantara <pcacjr(a)zytor.com&gt;
---
 hw/acpi/Makefile.objs  |   1 +
 hw/acpi/ich9.c         |  36 ++++++++++
 hw/acpi/tco.c          | 188 +++++++++++++++++++++++++++++++++++++++++++++++++
 hw/isa/lpc_ich9.c      |  10 +++
 include/hw/acpi/ich9.h |   4 ++
 include/hw/acpi/tco.h  | 139 ++++++++++++++++++++++++++++++++++++
 include/hw/i386/ich9.h |   8 +++
 7 files changed, 386 insertions(+)
 create mode 100644 hw/acpi/tco.c
 create mode 100644 include/hw/acpi/tco.h

diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index b9fefa7..a32b7f8 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -1,4 +1,5 @@
 common-obj-$(CONFIG_ACPI) += core.o piix4.o ich9.o pcihp.o cpu_hotplug.o
+common-obj-$(CONFIG_ACPI) += tco.o
 common-obj-$(CONFIG_ACPI) += memory_hotplug.o
 common-obj-$(CONFIG_ACPI) += acpi_interface.o
 common-obj-$(CONFIG_ACPI) += bios-linker-loader.o
diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
index 84e5bb8..8c4364b 100644
--- a/hw/acpi/ich9.c
+++ b/hw/acpi/ich9.c
@@ -30,6 +30,7 @@
 #include "qemu/timer.h"
 #include "sysemu/sysemu.h"
 #include "hw/acpi/acpi.h"
+#include "hw/acpi/tco.h"
 #include "sysemu/kvm.h"
 #include "exec/address-spaces.h"
 
@@ -92,8 +93,15 @@ static void ich9_smi_writel(void *opaque, hwaddr addr, uint64_t val,
                             unsigned width)
 {
     ICH9LPCPMRegs *pm = opaque;
+    TCOIORegs *tr = &pm->tco_regs;
+
     switch (addr) {
     case 0:
+        /* once TCO_LOCK bit is set, TCO_EN bit cannot be overwritten */
+        if (tr->tco.cnt1 & TCO_LOCK) {
+            val &= ~ICH9_PMIO_SMI_EN_TCO_EN;
+            val |= pm->smi_en & ICH9_PMIO_SMI_EN_TCO_EN;
+        }
         pm->smi_en = val;
         break;
     }
@@ -107,6 +115,29 @@ static const MemoryRegionOps ich9_smi_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
 };
 
+static uint64_t ich9_tco_readw(void *opaque, hwaddr addr, unsigned width)
+{
+    ICH9LPCPMRegs *pm = opaque;
+    return acpi_pm_tco_ioport_readw(&pm->tco_regs, addr);
+}
+
+static void ich9_tco_writew(void *opaque, hwaddr addr, uint64_t val,
+                            unsigned width)
+{
+    ICH9LPCPMRegs *pm = opaque;
+    acpi_pm_tco_ioport_writew(&pm->tco_regs, addr, val);
+}
+
+static const MemoryRegionOps ich9_tco_ops = {
+    .read = ich9_tco_readw,
+    .write = ich9_tco_writew,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 4,
+    .impl.min_access_size = 1,
+    .impl.max_access_size = 2,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+};
+
 void ich9_pm_iospace_update(ICH9LPCPMRegs *pm, uint32_t pm_io_base)
 {
     ICH9_DEBUG("to 0x%x\n", pm_io_base);
@@ -230,6 +261,11 @@ void ich9_pm_init(PCIDevice *lpc_pci, ICH9LPCPMRegs *pm,
                           "acpi-smi", 8);
     memory_region_add_subregion(&pm->io, ICH9_PMIO_SMI_EN, &pm->io_smi);
 
+    acpi_pm_tco_init(&pm->tco_regs);
+    memory_region_init_io(&pm->io_tco, OBJECT(lpc_pci), &ich9_tco_ops, pm,
+			  "sm-tco", ICH9_PMIO_TCO_LEN);
+    memory_region_add_subregion(&pm->io, ICH9_PMIO_TCO_RLD, &pm->io_tco);
+
     pm->irq = sci_irq;
     qemu_register_reset(pm_reset, pm);
     pm->powerdown_notifier.notify = pm_powerdown_req;
diff --git a/hw/acpi/tco.c b/hw/acpi/tco.c
new file mode 100644
index 0000000..3a44a95
--- /dev/null
+++ b/hw/acpi/tco.c
@@ -0,0 +1,188 @@
+/*
+ * QEMU ICH9 TCO emulation
+ *
+ * Copyright (c) 2015 Paulo Alcantara <pcacjr(a)zytor.com&gt;
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "qemu-common.h"
+#include "sysemu/watchdog.h"
+#include "hw/i386/ich9.h"
+
+#include "hw/acpi/tco.h"
+
+//#define DEBUG
+
+#ifdef DEBUG
+#define TCO_DEBUG(fmt, ...)                                     \
+    do {                                                        \
+        fprintf(stderr, "%s "fmt, __func__, ## __VA_ARGS__);    \
+    } while (0)
+#else
+#define TCO_DEBUG(fmt, ...) do { } while (0)
+#endif
+
+static QEMUTimer *tco_timer;
+static unsigned int timeouts_no;
+
+static inline void tco_timer_reload(void)
+{
+    int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+
+    timer_del(tco_timer);
+    timer_mod(tco_timer, now + tco_ticks_per_sec());
+}
+
+static inline void tco_timer_stop(void)
+{
+    timer_del(tco_timer);
+}
+
+static void tco_timer_expired(void *opaque)
+{
+    TCOIORegs *tr = opaque;
+    ICH9LPCPMRegs *pm = container_of(tr, ICH9LPCPMRegs, tco_regs);
+    ICH9LPCState *lpc = container_of(pm, ICH9LPCState, pm);
+    uint32_t gcs = pci_get_long(lpc->chip_config + ICH9_LPC_RCBA_GCS);
+
+    tr->tco.rld--;
+    if (tr->tco.rld & TCO_RLD_MASK) {
+        goto out;
+    }
+
+    tr->tco.sts1 |= TCO_TIMEOUT;
+    if (++timeouts_no == 2) {
+        tr->tco.sts1 |= TCO_SECOND_TO_STS;
+        tr->tco.sts1 |= TCO_BOOT_STS;
+        timeouts_no = 0;
+
+        if (!(gcs & ICH9_LPC_RCBA_GCS_NO_REBOOT)) {
+            watchdog_perform_action();
+            tco_timer_stop();
+            return;
+        }
+    }
+    tr->tco.rld = tr->tco.tmr;
+
+    if (pm->smi_en & ICH9_PMIO_SMI_EN_TCO_EN) {
+        ich9_generate_smi();
+    } else {
+        ich9_generate_nmi();
+    }
+
+out:
+    tco_timer_reload();
+}
+
+void acpi_pm_tco_init(TCOIORegs *tr)
+{
+    *tr = TCO_IO_REGS_DEFAULTS_INIT();
+    tco_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, tco_timer_expired, tr);
+}
+
+uint32_t acpi_pm_tco_ioport_readw(TCOIORegs *tr, uint32_t addr)
+{
+    switch (addr) {
+    case TCO_RLD:
+        return tr->tco.rld;
+    case TCO_DAT_IN:
+        return tr->tco.din;
+    case TCO_DAT_OUT:
+        return tr->tco.dout;
+    case TCO1_STS:
+        return tr->tco.sts1;
+    case TCO2_STS:
+        return tr->tco.sts2;
+    case TCO1_CNT:
+        return tr->tco.cnt1;
+    case TCO2_CNT:
+        return tr->tco.cnt2;
+    case TCO_MESSAGE1:
+        return tr->tco.msg1;
+    case TCO_MESSAGE2:
+        return tr->tco.msg2;
+    case TCO_WDCNT:
+        return tr->tco.wdcnt;
+    case TCO_TMR:
+        return tr->tco.tmr;
+    case SW_IRQ_GEN:
+        return tr->sw_irq_gen;
+    }
+    return 0;
+}
+
+void acpi_pm_tco_ioport_writew(TCOIORegs *tr, uint32_t addr, uint32_t val)
+{
+    switch (addr) {
+    case TCO_RLD:
+        timeouts_no = 0;
+        if (can_start_tco_timer(tr)) {
+            tr->tco.rld = tr->tco.tmr;
+            tco_timer_reload();
+        } else {
+            tr->tco.rld = val;
+        }
+        break;
+    case TCO_DAT_IN:
+        tr->tco.din = val;
+        tr->tco.sts1 |= SW_TCO_SMI;
+        ich9_generate_smi();
+        break;
+    case TCO_DAT_OUT:
+        tr->tco.dout = val;
+        tr->tco.sts1 |= TCO_INT_STS;
+        /* TODO: cause an interrupt, as selected by the TCO_INT_SEL bits */
+        break;
+    case TCO1_STS:
+        tr->tco.sts1 = val & TCO1_STS_MASK;
+        break;
+    case TCO2_STS:
+        tr->tco.sts2 = val & TCO2_STS_MASK;
+        break;
+    case TCO1_CNT:
+        val &= TCO1_CNT_MASK;
+        /* TCO_LOCK bit cannot be changed once set */
+        tr->tco.cnt1 = (val & ~TCO_LOCK) | (tr->tco.cnt1 & TCO_LOCK);
+        if (can_start_tco_timer(tr)) {
+            tr->tco.rld = tr->tco.tmr;
+            tco_timer_reload();
+        } else {
+            tco_timer_stop();
+        }
+        break;
+    case TCO2_CNT:
+        tr->tco.cnt2 = val;
+        break;
+    case TCO_MESSAGE1:
+        tr->tco.msg1 = val;
+        break;
+    case TCO_MESSAGE2:
+        tr->tco.msg2 = val;
+        break;
+    case TCO_WDCNT:
+        tr->tco.wdcnt = val;
+        break;
+    case TCO_TMR:
+        tr->tco.tmr = val;
+        break;
+    case SW_IRQ_GEN:
+        tr->sw_irq_gen = val;
+        break;
+    }
+}
diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index dba7585..7bfb683 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -313,6 +313,16 @@ PCIINTxRoute ich9_route_intx_pin_to_irq(void *opaque, int pirq_pin)
     return route;
 }
 
+void ich9_generate_smi(void)
+{
+    cpu_interrupt(first_cpu, CPU_INTERRUPT_SMI);
+}
+
+void ich9_generate_nmi(void)
+{
+    cpu_interrupt(first_cpu, CPU_INTERRUPT_NMI);
+}
+
 static int ich9_lpc_sci_irq(ICH9LPCState *lpc)
 {
     switch (lpc->d.config[ICH9_LPC_ACPI_CTRL] &
diff --git a/include/hw/acpi/ich9.h b/include/hw/acpi/ich9.h
index c2d3dba..31c74af 100644
--- a/include/hw/acpi/ich9.h
+++ b/include/hw/acpi/ich9.h
@@ -25,6 +25,7 @@
 #include "hw/acpi/cpu_hotplug.h"
 #include "hw/acpi/memory_hotplug.h"
 #include "hw/acpi/acpi_dev_interface.h"
+#include "hw/acpi/tco.h"
 
 typedef struct ICH9LPCPMRegs {
     /*
@@ -37,6 +38,7 @@ typedef struct ICH9LPCPMRegs {
     MemoryRegion io;
     MemoryRegion io_gpe;
     MemoryRegion io_smi;
+    MemoryRegion io_tco;
 
     uint32_t smi_en;
     uint32_t smi_sts;
@@ -53,6 +55,8 @@ typedef struct ICH9LPCPMRegs {
     uint8_t disable_s3;
     uint8_t disable_s4;
     uint8_t s4_val;
+
+    TCOIORegs tco_regs;
 } ICH9LPCPMRegs;
 
 void ich9_pm_init(PCIDevice *lpc_pci, ICH9LPCPMRegs *pm,
diff --git a/include/hw/acpi/tco.h b/include/hw/acpi/tco.h
new file mode 100644
index 0000000..700532c
--- /dev/null
+++ b/include/hw/acpi/tco.h
@@ -0,0 +1,139 @@
+/*
+ * QEMU ICH9 TCO emulation
+ *
+ * Copyright (c) 2015 Paulo Alcantara <pcacjr(a)zytor.com&gt;
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef HW_ACPI_TCO_H
+#define HW_ACPI_TCO_H
+
+#include "qemu/typedefs.h"
+#include "qemu-common.h"
+
+/* TCO I/O register offsets */
+enum {
+    TCO_RLD           = 0x00,
+    TCO_DAT_IN        = 0x02,
+    TCO_DAT_OUT       = 0x03,
+    TCO1_STS          = 0x04,
+    TCO2_STS          = 0x06,
+    TCO1_CNT          = 0x08,
+    TCO2_CNT          = 0x0a,
+    TCO_MESSAGE1      = 0x0c,
+    TCO_MESSAGE2      = 0x0d,
+    TCO_WDCNT         = 0x0e,
+    SW_IRQ_GEN        = 0x10,
+    TCO_TMR           = 0x12,
+};
+
+/* TCO I/O register defaults */
+enum {
+    TCO_RLD_DEFAULT         = 0x0000,
+    TCO_DAT_IN_DEFAULT      = 0x00,
+    TCO_DAT_OUT_DEFAULT     = 0x00,
+    TCO1_STS_DEFAULT        = 0x0000,
+    TCO2_STS_DEFAULT        = 0x0000,
+    TCO1_CNT_DEFAULT        = 0x0000,
+    TCO2_CNT_DEFAULT        = 0x0008,
+    TCO_MESSAGE1_DEFAULT    = 0x00,
+    TCO_MESSAGE2_DEFAULT    = 0x00,
+    TCO_WDCNT_DEFAULT       = 0x00,
+    TCO_TMR_DEFAULT         = 0x0004,
+    SW_IRQ_GEN_DEFAULT      = 0x03,
+};
+
+/* TCO I/O register control/status bits */
+enum {
+    SW_TCO_SMI           = (1 << 1),
+    TCO_INT_STS          = (1 << 2),
+    TCO_LOCK             = (1 << 12),
+    TCO_TMR_HLT          = (1 << 11),
+    TCO_TIMEOUT          = (1 << 3),
+    TCO_SECOND_TO_STS    = (1 << 1),
+    TCO_BOOT_STS         = (1 << 2),
+};
+
+/* TCO I/O registers mask bits */
+enum {
+    TCO_RLD_MASK     = 0x3ff,
+    TCO1_STS_MASK    = 0xe870,
+    TCO2_STS_MASK    = 0xfff8,
+    TCO1_CNT_MASK    = 0xfeff,
+    TCO_TMR_MASK     = 0x3ff,
+};
+
+typedef struct TCOIORegs {
+    struct {
+        uint16_t rld;
+        uint8_t din;
+        uint8_t dout;
+        uint16_t sts1;
+        uint16_t sts2;
+        uint16_t cnt1;
+        uint16_t cnt2;
+        uint8_t msg1;
+        uint8_t msg2;
+        uint8_t wdcnt;
+        uint16_t tmr;
+    } tco;
+    uint8_t sw_irq_gen;
+} TCOIORegs;
+
+#define TCO_IO_REGS_DEFAULTS_INIT()             \
+    (TCOIORegs) {                               \
+        .tco = {                                \
+            .rld      = TCO_RLD_DEFAULT,        \
+            .din      = TCO_DAT_IN_DEFAULT,     \
+            .dout     = TCO_DAT_OUT_DEFAULT,    \
+            .sts1     = TCO1_STS_DEFAULT,       \
+            .sts2     = TCO2_STS_DEFAULT,       \
+            .cnt1     = TCO1_CNT_DEFAULT,       \
+            .cnt2     = TCO2_CNT_DEFAULT,       \
+            .msg1     = TCO_MESSAGE1_DEFAULT,   \
+            .msg2     = TCO_MESSAGE2_DEFAULT,   \
+            .wdcnt    = TCO_WDCNT_DEFAULT,      \
+            .tmr      = TCO_TMR_DEFAULT,        \
+        },                                      \
+        .sw_irq_gen = SW_IRQ_GEN_DEFAULT        \
+    }
+
+/* tco.c */
+void acpi_pm_tco_init(TCOIORegs *tr);
+uint32_t acpi_pm_tco_ioport_readw(TCOIORegs *tr, uint32_t addr);
+void acpi_pm_tco_ioport_writew(TCOIORegs *tr, uint32_t addr, uint32_t val);
+
+/* As per ICH9 spec, the internal timer has an error of ~0.6s on every tick */
+static inline int64_t tco_ticks_per_sec(void)
+{
+    return 600000000LL;
+}
+
+static inline int is_valid_tco_time(uint32_t val)
+{
+    /* values of 0 or 1 will be ignored by ICH */
+    return val > 1;
+}
+
+static inline int can_start_tco_timer(TCOIORegs *tr)
+{
+    return !(tr->tco.cnt1 & TCO_TMR_HLT) &&
is_valid_tco_time(tr->tco.tmr);
+}
+
+#endif /* HW_ACPI_TCO_H */
diff --git a/include/hw/i386/ich9.h b/include/hw/i386/ich9.h
index f4e522c..f41cca6 100644
--- a/include/hw/i386/ich9.h
+++ b/include/hw/i386/ich9.h
@@ -20,6 +20,9 @@ PCIINTxRoute ich9_route_intx_pin_to_irq(void *opaque, int pirq_pin);
 void ich9_lpc_pm_init(PCIDevice *pci_lpc);
 I2CBus *ich9_smb_init(PCIBus *bus, int devfn, uint32_t smb_io_base);
 
+void ich9_generate_smi(void);
+void ich9_generate_nmi(void);
+
 #define ICH9_CC_SIZE                            (16 * 1024)     /* 16KB */
 
 #define TYPE_ICH9_LPC_DEVICE "ICH9-LPC"
@@ -156,6 +159,8 @@ Object *ich9_lpc_find(void);
 #define ICH9_LPC_RCBA_BA_MASK                   Q35_MASK(32, 31, 14)
 #define ICH9_LPC_RCBA_EN                        0x1
 #define ICH9_LPC_RCBA_DEFAULT                   0x0
+#define ICH9_LPC_RCBA_GCS                       0x3410
+#define ICH9_LPC_RCBA_GCS_NO_REBOOT             (1 << 5)
 
 #define ICH9_LPC_PIC_NUM_PINS                   16
 #define ICH9_LPC_IOAPIC_NUM_PINS                24
@@ -180,7 +185,10 @@ Object *ich9_lpc_find(void);
 #define ICH9_PMIO_GPE0_LEN                      16
 #define ICH9_PMIO_SMI_EN                        0x30
 #define ICH9_PMIO_SMI_EN_APMC_EN                (1 << 5)
+#define ICH9_PMIO_SMI_EN_TCO_EN                 (1 << 13)
 #define ICH9_PMIO_SMI_STS                       0x34
+#define ICH9_PMIO_TCO_RLD                       0x60
+#define ICH9_PMIO_TCO_LEN                       32
 
 /* FADT ACPI_ENABLE/ACPI_DISABLE */
 #define ICH9_APM_ACPI_ENABLE                    0x2
-- 
2.1.0



    

[PATCH 1/3] ich9: add TCO interface emulation