[PULL 31/33] hw/misc: Introduce AMD/Xilix Versal TRNG device

From: Peter Maydell <peter.maydell@linaro.org>
To: qemu-devel@nongnu.org
Subject: [PULL 31/33] hw/misc: Introduce AMD/Xilix Versal TRNG device
Date: Thu,  2 Nov 2023 17:38:33 +0000	[thread overview]
Message-ID: <20231102173835.609985-32-peter.maydell@linaro.org> (raw)
In-Reply-To: <20231102173835.609985-1-peter.maydell@linaro.org>

From: Tong Ho <tong.ho@amd.com>

This adds a non-cryptographic grade implementation of the
model for the True Random Number Generator (TRNG) component
in AMD/Xilinx Versal device family.

This implements all 3 modes defined by the actual hardware
specs, all of which selectable by guest software at will
at anytime:
1) PRNG mode, in which the generated sequence is required to
   be reproducible after reseeded by the same 384-bit value
   as supplied by guest software.
2) Test mode, in which the generated sequence is required to
   be reproducible ater reseeded by the same 128-bit test
   seed supplied by guest software.
3) TRNG mode, in which non-reproducible sequence is generated
   based on periodic reseed by a suitable entropy source.

This model is only intended for non-real world testing of
guest software, where cryptographically strong PRNG or TRNG
is not needed.

This model supports versions 1 & 2 of the device, with
default to be version 2; the 'hw-version' uint32 property
can be set to 0x0100 to override the default.

Other implemented properties:
- 'forced-prng', uint64
  When set to non-zero, mode 3's entropy source is implemented
  as a deterministic sequence based on the given value and other
  deterministic parameters.
  This option allows the emulation to test guest software using
  mode 3 and to reproduce data-dependent defects.

- 'fips-fault-events', uint32, bit-mask
  bit 3: Triggers the SP800-90B entropy health test fault irq
  bit 1: Triggers the FIPS 140-2 continuous test fault irq

Signed-off-by: Tong Ho <tong.ho@amd.com>
Message-id: 20231031184611.3029156-2-tong.ho@amd.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 include/hw/misc/xlnx-versal-trng.h |  58 +++
 hw/misc/xlnx-versal-trng.c         | 717 +++++++++++++++++++++++++++++
 hw/misc/Kconfig                    |   3 +
 hw/misc/meson.build                |   3 +
 4 files changed, 781 insertions(+)
 create mode 100644 include/hw/misc/xlnx-versal-trng.h
 create mode 100644 hw/misc/xlnx-versal-trng.c

diff --git a/include/hw/misc/xlnx-versal-trng.h b/include/hw/misc/xlnx-versal-trng.h
new file mode 100644
index 00000000000..0bcef8a6132
--- /dev/null
+++ b/include/hw/misc/xlnx-versal-trng.h
@@ -0,0 +1,58 @@
+/*
+ * Non-crypto strength model of the True Random Number Generator
+ * in the AMD/Xilinx Versal device family.
+ *
+ * Copyright (c) 2017-2020 Xilinx Inc.
+ * Copyright (c) 2023 Advanced Micro Devices, Inc.
+ *
+ * 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 XLNX_VERSAL_TRNG_H
+#define XLNX_VERSAL_TRNG_H
+
+#include "hw/irq.h"
+#include "hw/sysbus.h"
+#include "hw/register.h"
+
+#define TYPE_XLNX_VERSAL_TRNG "xlnx.versal-trng"
+OBJECT_DECLARE_SIMPLE_TYPE(XlnxVersalTRng, XLNX_VERSAL_TRNG);
+
+#define RMAX_XLNX_VERSAL_TRNG ((0xf0 / 4) + 1)
+
+typedef struct XlnxVersalTRng {
+    SysBusDevice parent_obj;
+    qemu_irq irq;
+    GRand *prng;
+
+    uint32_t hw_version;
+    uint32_t forced_faults;
+
+    uint32_t rand_count;
+    uint64_t rand_reseed;
+
+    uint64_t forced_prng_seed;
+    uint64_t forced_prng_count;
+    uint64_t tst_seed[2];
+
+    uint32_t regs[RMAX_XLNX_VERSAL_TRNG];
+    RegisterInfo regs_info[RMAX_XLNX_VERSAL_TRNG];
+} XlnxVersalTRng;
+
+#undef RMAX_XLNX_VERSAL_TRNG
+#endif
diff --git a/hw/misc/xlnx-versal-trng.c b/hw/misc/xlnx-versal-trng.c
new file mode 100644
index 00000000000..4d41c262c48
--- /dev/null
+++ b/hw/misc/xlnx-versal-trng.c
@@ -0,0 +1,717 @@
+/*
+ * Non-crypto strength model of the True Random Number Generator
+ * in the AMD/Xilinx Versal device family.
+ *
+ * Copyright (c) 2017-2020 Xilinx Inc.
+ * Copyright (c) 2023 Advanced Micro Devices, Inc.
+ *
+ * Written by Edgar E. Iglesias <edgar.iglesias@xilinx.com>
+ *
+ * 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/osdep.h"
+#include "hw/misc/xlnx-versal-trng.h"
+
+#include "qemu/bitops.h"
+#include "qemu/log.h"
+#include "qemu/error-report.h"
+#include "qemu/guest-random.h"
+#include "qemu/timer.h"
+#include "qapi/visitor.h"
+#include "migration/vmstate.h"
+#include "hw/qdev-properties.h"
+
+#ifndef XLNX_VERSAL_TRNG_ERR_DEBUG
+#define XLNX_VERSAL_TRNG_ERR_DEBUG 0
+#endif
+
+REG32(INT_CTRL, 0x0)
+    FIELD(INT_CTRL, CERTF_RST, 5, 1)
+    FIELD(INT_CTRL, DTF_RST, 4, 1)
+    FIELD(INT_CTRL, DONE_RST, 3, 1)
+    FIELD(INT_CTRL, CERTF_EN, 2, 1)
+    FIELD(INT_CTRL, DTF_EN, 1, 1)
+    FIELD(INT_CTRL, DONE_EN, 0, 1)
+REG32(STATUS, 0x4)
+    FIELD(STATUS, QCNT, 9, 3)
+    FIELD(STATUS, EAT, 4, 5)
+    FIELD(STATUS, CERTF, 3, 1)
+    FIELD(STATUS, DTF, 1, 1)
+    FIELD(STATUS, DONE, 0, 1)
+REG32(CTRL, 0x8)
+    FIELD(CTRL, PERSODISABLE, 10, 1)
+    FIELD(CTRL, SINGLEGENMODE, 9, 1)
+    FIELD(CTRL, EUMODE, 8, 1)
+    FIELD(CTRL, PRNGMODE, 7, 1)
+    FIELD(CTRL, TSTMODE, 6, 1)
+    FIELD(CTRL, PRNGSTART, 5, 1)
+    FIELD(CTRL, EATAU, 4, 1)
+    FIELD(CTRL, PRNGXS, 3, 1)
+    FIELD(CTRL, TRSSEN, 2, 1)
+    FIELD(CTRL, QERTUEN, 1, 1)
+    FIELD(CTRL, PRNGSRST, 0, 1)
+REG32(CTRL_2, 0xc)
+    FIELD(CTRL_2, REPCOUNTTESTCUTOFF, 8, 9)
+    FIELD(CTRL_2, RESERVED_7_5, 5, 3)
+    FIELD(CTRL_2, DIT, 0, 5)
+REG32(CTRL_3, 0x10)
+    FIELD(CTRL_3, ADAPTPROPTESTCUTOFF, 8, 10)
+    FIELD(CTRL_3, DLEN, 0, 8)
+REG32(CTRL_4, 0x14)
+    FIELD(CTRL_4, SINGLEBITRAW, 0, 1)
+REG32(EXT_SEED_0, 0x40)
+REG32(EXT_SEED_1, 0x44)
+REG32(EXT_SEED_2, 0x48)
+REG32(EXT_SEED_3, 0x4c)
+REG32(EXT_SEED_4, 0x50)
+REG32(EXT_SEED_5, 0x54)
+REG32(EXT_SEED_6, 0x58)
+REG32(EXT_SEED_7, 0x5c)
+REG32(EXT_SEED_8, 0x60)
+REG32(EXT_SEED_9, 0x64)
+REG32(EXT_SEED_10, 0x68)
+REG32(EXT_SEED_11, 0x6c)
+REG32(PER_STRNG_0, 0x80)
+REG32(PER_STRNG_1, 0x84)
+REG32(PER_STRNG_2, 0x88)
+REG32(PER_STRNG_3, 0x8c)
+REG32(PER_STRNG_4, 0x90)
+REG32(PER_STRNG_5, 0x94)
+REG32(PER_STRNG_6, 0x98)
+REG32(PER_STRNG_7, 0x9c)
+REG32(PER_STRNG_8, 0xa0)
+REG32(PER_STRNG_9, 0xa4)
+REG32(PER_STRNG_10, 0xa8)
+REG32(PER_STRNG_11, 0xac)
+REG32(CORE_OUTPUT, 0xc0)
+REG32(RESET, 0xd0)
+    FIELD(RESET, VAL, 0, 1)
+REG32(OSC_EN, 0xd4)
+    FIELD(OSC_EN, VAL, 0, 1)
+REG32(TRNG_ISR, 0xe0)
+    FIELD(TRNG_ISR, SLVERR, 1, 1)
+    FIELD(TRNG_ISR, CORE_INT, 0, 1)
+REG32(TRNG_IMR, 0xe4)
+    FIELD(TRNG_IMR, SLVERR, 1, 1)
+    FIELD(TRNG_IMR, CORE_INT, 0, 1)
+REG32(TRNG_IER, 0xe8)
+    FIELD(TRNG_IER, SLVERR, 1, 1)
+    FIELD(TRNG_IER, CORE_INT, 0, 1)
+REG32(TRNG_IDR, 0xec)
+    FIELD(TRNG_IDR, SLVERR, 1, 1)
+    FIELD(TRNG_IDR, CORE_INT, 0, 1)
+REG32(SLV_ERR_CTRL, 0xf0)
+    FIELD(SLV_ERR_CTRL, ENABLE, 0, 1)
+
+#define R_MAX (R_SLV_ERR_CTRL + 1)
+
+QEMU_BUILD_BUG_ON(R_MAX * 4 != sizeof_field(XlnxVersalTRng, regs));
+
+#define TRNG_GUEST_ERROR(D, FMT, ...) \
+    do {                                                               \
+        g_autofree char *p = object_get_canonical_path(OBJECT(D));     \
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: " FMT, p, ## __VA_ARGS__); \
+    } while (0)
+
+#define TRNG_WARN(D, FMT, ...) \
+    do {                                                               \
+        g_autofree char *p = object_get_canonical_path(OBJECT(D));     \
+        warn_report("%s: " FMT, p, ## __VA_ARGS__);                    \
+    } while (0)
+
+static bool trng_older_than_v2(XlnxVersalTRng *s)
+{
+    return s->hw_version < 0x0200;
+}
+
+static bool trng_in_reset(XlnxVersalTRng *s)
+{
+    if (ARRAY_FIELD_EX32(s->regs, RESET, VAL)) {
+        return true;
+    }
+    if (ARRAY_FIELD_EX32(s->regs, CTRL, PRNGSRST)) {
+        return true;
+    }
+
+    return false;
+}
+
+static bool trng_test_enabled(XlnxVersalTRng *s)
+{
+    return ARRAY_FIELD_EX32(s->regs, CTRL, TSTMODE);
+}
+
+static bool trng_trss_enabled(XlnxVersalTRng *s)
+{
+    if (trng_in_reset(s)) {
+        return false;
+    }
+    if (!ARRAY_FIELD_EX32(s->regs, CTRL, TRSSEN)) {
+        return false;
+    }
+    if (!ARRAY_FIELD_EX32(s->regs, OSC_EN, VAL)) {
+        return false;
+    }
+
+    return true;
+}
+
+static void trng_seed_128(uint32_t *seed, uint64_t h00, uint64_t h64)
+{
+    seed[0] = extract64(h00, 0, 32);
+    seed[1] = extract64(h00, 32, 32);
+    seed[2] = extract64(h64, 0, 32);
+    seed[3] = extract64(h64, 32, 32);
+}
+
+static void trng_reseed(XlnxVersalTRng *s)
+{
+    bool ext_seed = ARRAY_FIELD_EX32(s->regs, CTRL, PRNGXS);
+    bool pers_disabled = ARRAY_FIELD_EX32(s->regs, CTRL, PERSODISABLE);
+
+    enum {
+        U384_U8 = 384 / 8,
+        U384_U32 = 384 / 32,
+    };
+
+    /*
+     * Maximum seed length is len(personalized string) + len(ext seed).
+     *
+     * g_rand_set_seed_array() takes array of uint32 in host endian.
+     */
+    guint32 gs[U384_U32 * 2], *seed = &gs[U384_U32];
+
+    /*
+     * A disabled personalized string is the same as
+     * a string with all zeros.
+     *
+     * The device's hardware spec defines 3 modes (all selectable
+     * by guest at will and at anytime):
+     * 1) External seeding
+     *    This is a PRNG mode, in which the produced sequence shall
+     *    be reproducible if reseeded by the same 384-bit seed, as
+     *    supplied by guest software.
+     * 2) Test seeding
+     *    This is a PRNG mode, in which the produced sequence shall
+     *    be reproducible if reseeded by a 128-bit test seed, as
+     *    supplied by guest software.
+     * 3) Truly-random seeding
+     *    This is the TRNG mode, in which the produced sequence is
+     *    periodically reseeded by a crypto-strength entropy source.
+     *
+     * To assist debugging of certain classes of software defects,
+     * this QEMU model implements a 4th mode,
+     * 4) Forced PRNG
+     *    When in this mode, a reproducible sequence is generated
+     *    if software has selected the TRNG mode (mode 2).
+     *
+     *    This emulation-only mode can only be selected by setting
+     *    the uint64 property 'forced-prng' to a non-zero value.
+     *    Guest software cannot select this mode.
+     */
+    memset(gs, 0, sizeof(gs));
+
+    if (!pers_disabled) {
+        memcpy(gs, &s->regs[R_PER_STRNG_0], U384_U8);
+    }
+
+    if (ext_seed) {
+        memcpy(seed, &s->regs[R_EXT_SEED_0], U384_U8);
+    } else if (trng_test_enabled(s)) {
+        trng_seed_128(seed, s->tst_seed[0], s->tst_seed[1]);
+    } else if (s->forced_prng_seed) {
+        s->forced_prng_count++;
+        trng_seed_128(seed, s->forced_prng_count, s->forced_prng_seed);
+    } else {
+        qemu_guest_getrandom_nofail(seed, U384_U8);
+    }
+
+    g_rand_set_seed_array(s->prng, gs, ARRAY_SIZE(gs));
+
+    s->rand_count = 0;
+    s->rand_reseed = 1ULL << 48;
+}
+
+static void trng_regen(XlnxVersalTRng *s)
+{
+    if (s->rand_reseed == 0) {
+        TRNG_GUEST_ERROR(s, "Too many generations without a reseed");
+        trng_reseed(s);
+    }
+    s->rand_reseed--;
+
+    /*
+     * In real hardware, each regen creates 256 bits, but QCNT
+     * reports a max of 4.
+     */
+    ARRAY_FIELD_DP32(s->regs, STATUS, QCNT, 4);
+    s->rand_count = 256 / 32;
+}
+
+static uint32_t trng_rdout(XlnxVersalTRng *s)
+{
+    assert(s->rand_count);
+
+    s->rand_count--;
+    if (s->rand_count < 4) {
+        ARRAY_FIELD_DP32(s->regs, STATUS, QCNT, s->rand_count);
+    }
+
+    return g_rand_int(s->prng);
+}
+
+static void trng_irq_update(XlnxVersalTRng *s)
+{
+    bool pending = s->regs[R_TRNG_ISR] & ~s->regs[R_TRNG_IMR];
+    qemu_set_irq(s->irq, pending);
+}
+
+static void trng_isr_postw(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+    trng_irq_update(s);
+}
+
+static uint64_t trng_ier_prew(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+    uint32_t val = val64;
+
+    s->regs[R_TRNG_IMR] &= ~val;
+    trng_irq_update(s);
+    return 0;
+}
+
+static uint64_t trng_idr_prew(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+    uint32_t val = val64;
+
+    s->regs[R_TRNG_IMR] |= val;
+    trng_irq_update(s);
+    return 0;
+}
+
+static void trng_core_int_update(XlnxVersalTRng *s)
+{
+    bool pending = false;
+    uint32_t st = s->regs[R_STATUS];
+    uint32_t en = s->regs[R_INT_CTRL];
+
+    if (FIELD_EX32(st, STATUS, CERTF) && FIELD_EX32(en, INT_CTRL, CERTF_EN)) {
+        pending = true;
+    }
+
+    if (FIELD_EX32(st, STATUS, DTF) && FIELD_EX32(en, INT_CTRL, DTF_EN)) {
+        pending = true;
+    }
+
+    if (FIELD_EX32(st, STATUS, DONE) && FIELD_EX32(en, INT_CTRL, DONE_EN)) {
+        pending = true;
+    }
+
+    ARRAY_FIELD_DP32(s->regs, TRNG_ISR, CORE_INT, pending);
+    trng_irq_update(s);
+}
+
+static void trng_int_ctrl_postw(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+    uint32_t v32 = val64;
+    uint32_t clr_mask = 0;
+
+    if (FIELD_EX32(v32, INT_CTRL, CERTF_RST)) {
+        clr_mask |= R_STATUS_CERTF_MASK;
+    }
+    if (FIELD_EX32(v32, INT_CTRL, DTF_RST)) {
+        clr_mask |= R_STATUS_DTF_MASK;
+    }
+    if (FIELD_EX32(v32, INT_CTRL, DONE_RST)) {
+        clr_mask |= R_STATUS_DONE_MASK;
+    }
+
+    s->regs[R_STATUS] &= ~clr_mask;
+    trng_core_int_update(s);
+}
+
+static void trng_done(XlnxVersalTRng *s)
+{
+    ARRAY_FIELD_DP32(s->regs, STATUS, DONE, true);
+    trng_core_int_update(s);
+}
+
+static void trng_fault_event_set(XlnxVersalTRng *s, uint32_t events)
+{
+    bool pending = false;
+
+    /* Disabled TRSS cannot generate any fault event */
+    if (!trng_trss_enabled(s)) {
+        return;
+    }
+
+    if (FIELD_EX32(events, STATUS, CERTF)) {
+        /* In older version, ERTU must be enabled explicitly to get CERTF */
+        if (trng_older_than_v2(s) &&
+            !ARRAY_FIELD_EX32(s->regs, CTRL, QERTUEN)) {
+            TRNG_WARN(s, "CERTF injection ignored: ERTU disabled");
+        } else {
+            ARRAY_FIELD_DP32(s->regs, STATUS, CERTF, true);
+            pending = true;
+        }
+    }
+
+    if (FIELD_EX32(events, STATUS, DTF)) {
+        ARRAY_FIELD_DP32(s->regs, STATUS, DTF, true);
+        pending = true;
+    }
+
+    if (pending) {
+        trng_core_int_update(s);
+    }
+}
+
+static void trng_soft_reset(XlnxVersalTRng *s)
+{
+    s->rand_count = 0;
+    s->regs[R_STATUS] = 0;
+
+    ARRAY_FIELD_DP32(s->regs, TRNG_ISR, CORE_INT, 0);
+}
+
+static void trng_ctrl_postw(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+
+    if (trng_in_reset(s)) {
+        return;
+    }
+
+    if (FIELD_EX32(val64, CTRL, PRNGSRST)) {
+        trng_soft_reset(s);
+        trng_irq_update(s);
+        return;
+    }
+
+    if (!FIELD_EX32(val64, CTRL, PRNGSTART)) {
+        return;
+    }
+
+    if (FIELD_EX32(val64, CTRL, PRNGMODE)) {
+        trng_regen(s);
+    } else {
+        trng_reseed(s);
+    }
+
+    trng_done(s);
+}
+
+static void trng_ctrl4_postw(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+
+    /* Only applies to test mode with TRSS enabled */
+    if (!trng_test_enabled(s) || !trng_trss_enabled(s)) {
+        return;
+    }
+
+    /* Shift in a single bit.  */
+    s->tst_seed[1] <<= 1;
+    s->tst_seed[1] |= s->tst_seed[0] >> 63;
+    s->tst_seed[0] <<= 1;
+    s->tst_seed[0] |= val64 & 1;
+
+    trng_reseed(s);
+    trng_regen(s);
+}
+
+static uint64_t trng_core_out_postr(RegisterInfo *reg, uint64_t val)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+    bool oneshot = ARRAY_FIELD_EX32(s->regs, CTRL, SINGLEGENMODE);
+    bool start = ARRAY_FIELD_EX32(s->regs, CTRL, PRNGSTART);
+    uint32_t r = 0xbad;
+
+    if (trng_in_reset(s)) {
+        TRNG_GUEST_ERROR(s, "Reading random number while in reset!");
+        return r;
+    }
+
+    if (s->rand_count == 0) {
+        TRNG_GUEST_ERROR(s, "Reading random number when unavailable!");
+        return r;
+    }
+
+    r = trng_rdout(s);
+
+    /* Automatic mode regenerates when half the output reg is empty.  */
+    if (!oneshot && start && s->rand_count <= 3) {
+        trng_regen(s);
+    }
+
+    return r;
+}
+
+static void trng_reset(XlnxVersalTRng *s)
+{
+    unsigned int i;
+
+    s->forced_prng_count = 0;
+
+    for (i = 0; i < ARRAY_SIZE(s->regs_info); ++i) {
+        register_reset(&s->regs_info[i]);
+    }
+    trng_soft_reset(s);
+    trng_irq_update(s);
+}
+
+static uint64_t trng_reset_prew(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg->opaque);
+
+    if (!ARRAY_FIELD_EX32(s->regs, RESET, VAL) &&
+        FIELD_EX32(val64, RESET, VAL)) {
+        trng_reset(s);
+    }
+
+    return val64;
+}
+
+static uint64_t trng_register_read(void *opaque, hwaddr addr, unsigned size)
+{
+    /*
+     * Guest provided seed and personalized strings cannot be
+     * read back, and read attempts return value of A_STATUS.
+     */
+    switch (addr) {
+    case A_EXT_SEED_0 ... A_PER_STRNG_11:
+        addr = A_STATUS;
+        break;
+    }
+
+    return register_read_memory(opaque, addr, size);
+}
+
+static void trng_register_write(void *opaque, hwaddr addr,
+                                uint64_t value, unsigned size)
+{
+    RegisterInfoArray *reg_array = opaque;
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(reg_array->r[0]->opaque);
+
+    if (trng_older_than_v2(s)) {
+        switch (addr) {
+        case A_CTRL:
+            value = FIELD_DP64(value, CTRL, PERSODISABLE, 0);
+            value = FIELD_DP64(value, CTRL, SINGLEGENMODE, 0);
+            break;
+        case A_CTRL_2:
+        case A_CTRL_3:
+        case A_CTRL_4:
+            return;
+        }
+    } else {
+        switch (addr) {
+        case A_CTRL:
+            value = FIELD_DP64(value, CTRL, EATAU, 0);
+            value = FIELD_DP64(value, CTRL, QERTUEN, 0);
+            break;
+        }
+    }
+
+    register_write_memory(opaque, addr, value, size);
+}
+
+static RegisterAccessInfo trng_regs_info[] = {
+    {   .name = "INT_CTRL",  .addr = A_INT_CTRL,
+        .post_write = trng_int_ctrl_postw,
+    },{ .name = "STATUS",  .addr = A_STATUS,
+        .ro = 0xfff,
+    },{ .name = "CTRL",  .addr = A_CTRL,
+        .post_write = trng_ctrl_postw,
+    },{ .name = "CTRL_2",  .addr = A_CTRL_2,
+        .reset = 0x210c,
+    },{ .name = "CTRL_3",  .addr = A_CTRL_3,
+        .reset = 0x26f09,
+    },{ .name = "CTRL_4",  .addr = A_CTRL_4,
+        .post_write = trng_ctrl4_postw,
+    },{ .name = "EXT_SEED_0",  .addr = A_EXT_SEED_0,
+    },{ .name = "EXT_SEED_1",  .addr = A_EXT_SEED_1,
+    },{ .name = "EXT_SEED_2",  .addr = A_EXT_SEED_2,
+    },{ .name = "EXT_SEED_3",  .addr = A_EXT_SEED_3,
+    },{ .name = "EXT_SEED_4",  .addr = A_EXT_SEED_4,
+    },{ .name = "EXT_SEED_5",  .addr = A_EXT_SEED_5,
+    },{ .name = "EXT_SEED_6",  .addr = A_EXT_SEED_6,
+    },{ .name = "EXT_SEED_7",  .addr = A_EXT_SEED_7,
+    },{ .name = "EXT_SEED_8",  .addr = A_EXT_SEED_8,
+    },{ .name = "EXT_SEED_9",  .addr = A_EXT_SEED_9,
+    },{ .name = "EXT_SEED_10",  .addr = A_EXT_SEED_10,
+    },{ .name = "EXT_SEED_11",  .addr = A_EXT_SEED_11,
+    },{ .name = "PER_STRNG_0",  .addr = A_PER_STRNG_0,
+    },{ .name = "PER_STRNG_1",  .addr = A_PER_STRNG_1,
+    },{ .name = "PER_STRNG_2",  .addr = A_PER_STRNG_2,
+    },{ .name = "PER_STRNG_3",  .addr = A_PER_STRNG_3,
+    },{ .name = "PER_STRNG_4",  .addr = A_PER_STRNG_4,
+    },{ .name = "PER_STRNG_5",  .addr = A_PER_STRNG_5,
+    },{ .name = "PER_STRNG_6",  .addr = A_PER_STRNG_6,
+    },{ .name = "PER_STRNG_7",  .addr = A_PER_STRNG_7,
+    },{ .name = "PER_STRNG_8",  .addr = A_PER_STRNG_8,
+    },{ .name = "PER_STRNG_9",  .addr = A_PER_STRNG_9,
+    },{ .name = "PER_STRNG_10",  .addr = A_PER_STRNG_10,
+    },{ .name = "PER_STRNG_11",  .addr = A_PER_STRNG_11,
+    },{ .name = "CORE_OUTPUT",  .addr = A_CORE_OUTPUT,
+        .ro = 0xffffffff,
+        .post_read = trng_core_out_postr,
+    },{ .name = "RESET",  .addr = A_RESET,
+        .reset = 0x1,
+        .pre_write = trng_reset_prew,
+    },{ .name = "OSC_EN",  .addr = A_OSC_EN,
+    },{ .name = "TRNG_ISR",  .addr = A_TRNG_ISR,
+        .w1c = 0x3,
+        .post_write = trng_isr_postw,
+    },{ .name = "TRNG_IMR",  .addr = A_TRNG_IMR,
+        .reset = 0x3,
+        .ro = 0x3,
+    },{ .name = "TRNG_IER",  .addr = A_TRNG_IER,
+        .pre_write = trng_ier_prew,
+    },{ .name = "TRNG_IDR",  .addr = A_TRNG_IDR,
+        .pre_write = trng_idr_prew,
+    },{ .name = "SLV_ERR_CTRL",  .addr = A_SLV_ERR_CTRL,
+    }
+};
+
+static const MemoryRegionOps trng_ops = {
+    .read = trng_register_read,
+    .write = trng_register_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+};
+
+static void trng_init(Object *obj)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(obj);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+    RegisterInfoArray *reg_array;
+
+    reg_array =
+        register_init_block32(DEVICE(obj), trng_regs_info,
+                              ARRAY_SIZE(trng_regs_info),
+                              s->regs_info, s->regs,
+                              &trng_ops,
+                              XLNX_VERSAL_TRNG_ERR_DEBUG,
+                              R_MAX * 4);
+
+    sysbus_init_mmio(sbd, &reg_array->mem);
+    sysbus_init_irq(sbd, &s->irq);
+
+    s->prng = g_rand_new();
+}
+
+static void trng_unrealize(DeviceState *dev)
+{
+    XlnxVersalTRng *s = XLNX_VERSAL_TRNG(dev);
+
+    g_rand_free(s->prng);
+    s->prng = NULL;
+}
+
+static void trng_reset_hold(Object *obj)
+{
+    trng_reset(XLNX_VERSAL_TRNG(obj));
+}
+
+static void trng_prop_fault_event_set(Object *obj, Visitor *v,
+                                      const char *name, void *opaque,
+                                      Error **errp)
+{
+    Property *prop = opaque;
+    uint32_t *events = object_field_prop_ptr(obj, prop);
+
+    visit_type_uint32(v, name, events, errp);
+    if (*errp) {
+        return;
+    }
+
+    trng_fault_event_set(XLNX_VERSAL_TRNG(obj), *events);
+}
+
+static const PropertyInfo trng_prop_fault_events = {
+    .name = "uint32:bits",
+    .description = "Set to trigger TRNG fault events",
+    .set = trng_prop_fault_event_set,
+    .realized_set_allowed = true,
+};
+
+static PropertyInfo trng_prop_uint64; /* to extend qdev_prop_uint64 */
+
+static Property trng_props[] = {
+    DEFINE_PROP_UINT64("forced-prng", XlnxVersalTRng, forced_prng_seed, 0),
+    DEFINE_PROP_UINT32("hw-version", XlnxVersalTRng, hw_version, 0x0200),
+    DEFINE_PROP("fips-fault-events", XlnxVersalTRng, forced_faults,
+                trng_prop_fault_events, uint32_t),
+
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static const VMStateDescription vmstate_trng = {
+    .name = TYPE_XLNX_VERSAL_TRNG,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(rand_count, XlnxVersalTRng),
+        VMSTATE_UINT64(rand_reseed, XlnxVersalTRng),
+        VMSTATE_UINT64(forced_prng_count, XlnxVersalTRng),
+        VMSTATE_UINT64_ARRAY(tst_seed, XlnxVersalTRng, 2),
+        VMSTATE_UINT32_ARRAY(regs, XlnxVersalTRng, R_MAX),
+        VMSTATE_END_OF_LIST(),
+    }
+};
+
+static void trng_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+
+    dc->vmsd = &vmstate_trng;
+    dc->unrealize = trng_unrealize;
+    rc->phases.hold = trng_reset_hold;
+
+    /* Clone uint64 property with set allowed after realized */
+    trng_prop_uint64 = qdev_prop_uint64;
+    trng_prop_uint64.realized_set_allowed = true;
+    trng_props[0].info = &trng_prop_uint64;
+
+    device_class_set_props(dc, trng_props);
+}
+
+static const TypeInfo trng_info = {
+    .name          = TYPE_XLNX_VERSAL_TRNG,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(XlnxVersalTRng),
+    .class_init    = trng_class_init,
+    .instance_init = trng_init,
+};
+
+static void trng_register_types(void)
+{
+    type_register_static(&trng_info);
+}
+
+type_init(trng_register_types)
diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index dba41afe676..cc8a8c1418f 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -197,4 +197,7 @@ config DJMEMC
 config IOSB
     bool
 
+config XLNX_VERSAL_TRNG
+    bool
+
 source macio/Kconfig
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index f60de33f9af..36c20d5637f 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -104,6 +104,9 @@ system_ss.add(when: 'CONFIG_XLNX_VERSAL', if_true: files(
   'xlnx-cfi-if.c',
   'xlnx-versal-cframe-reg.c',
 ))
+system_ss.add(when: 'CONFIG_XLNX_VERSAL_TRNG', if_true: files(
+  'xlnx-versal-trng.c',
+))
 system_ss.add(when: 'CONFIG_STM32F2XX_SYSCFG', if_true: files('stm32f2xx_syscfg.c'))
 system_ss.add(when: 'CONFIG_STM32F4XX_SYSCFG', if_true: files('stm32f4xx_syscfg.c'))
 system_ss.add(when: 'CONFIG_STM32F4XX_EXTI', if_true: files('stm32f4xx_exti.c'))
-- 
2.34.1


