hw/nvram: Introduce Xilinx Versal eFuse device

This implements the Xilinx Versal eFuse, an one-time
field-programmable non-volatile storage device.  There is
only one such device in the Xilinx Versal product family.

This device has two separate mmio interfaces, a controller
and a flatten readback.

The controller provides interfaces for field-programming,
configuration, control, and status.

The flatten readback is a cache to provide a byte-accessible
read-only interface to efficiently read efuse array.

Co-authored-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Co-authored-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
Signed-off-by: Tong Ho <tong.ho@xilinx.com>
Message-id: 20210917052400.1249094-3-tong.ho@xilinx.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/nvram/Kconfig

@@ -22,3 +22,7 @@ config XLNX_EFUSE_CRC
 config XLNX_EFUSE
     bool
     select XLNX_EFUSE_CRC
+
+config XLNX_EFUSE_VERSAL
+    bool
+    select XLNX_EFUSE

hw/nvram/meson.build

@@ -11,5 +11,8 @@ softmmu_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx_otp.c'))
 softmmu_ss.add(when: 'CONFIG_NRF51_SOC', if_true: files('nrf51_nvm.c'))
 softmmu_ss.add(when: 'CONFIG_XLNX_EFUSE_CRC', if_true: files('xlnx-efuse-crc.c'))
 softmmu_ss.add(when: 'CONFIG_XLNX_EFUSE', if_true: files('xlnx-efuse.c'))
+softmmu_ss.add(when: 'CONFIG_XLNX_EFUSE_VERSAL', if_true: files(
+                                                   'xlnx-versal-efuse-cache.c',
+                                                   'xlnx-versal-efuse-ctrl.c'))
 
 specific_ss.add(when: 'CONFIG_PSERIES', if_true: files('spapr_nvram.c'))

hw/nvram/xlnx-versal-efuse-cache.c

@@ -0,0 +1,114 @@
+/*
+ * QEMU model of the EFuse_Cache
+ *
+ * Copyright (c) 2017 Xilinx 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.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/nvram/xlnx-versal-efuse.h"
+
+#include "qemu/log.h"
+#include "hw/qdev-properties.h"
+
+#define MR_SIZE 0xC00
+
+static uint64_t efuse_cache_read(void *opaque, hwaddr addr, unsigned size)
+{
+    XlnxVersalEFuseCache *s = XLNX_VERSAL_EFUSE_CACHE(opaque);
+    unsigned int w0 = QEMU_ALIGN_DOWN(addr * 8, 32);
+    unsigned int w1 = QEMU_ALIGN_DOWN((addr + size - 1) * 8, 32);
+
+    uint64_t ret;
+
+    assert(w0 == w1 || (w0 + 32) == w1);
+
+    ret = xlnx_versal_efuse_read_row(s->efuse, w1, NULL);
+    if (w0 < w1) {
+        ret <<= 32;
+        ret |= xlnx_versal_efuse_read_row(s->efuse, w0, NULL);
+    }
+
+    /* If 'addr' unaligned, the guest is always assumed to be little-endian. */
+    addr &= 3;
+    if (addr) {
+        ret >>= 8 * addr;
+    }
+
+    return ret;
+}
+
+static void efuse_cache_write(void *opaque, hwaddr addr, uint64_t value,
+                              unsigned size)
+{
+    /* No Register Writes allowed */
+    qemu_log_mask(LOG_GUEST_ERROR, "%s: efuse cache registers are read-only",
+                  __func__);
+}
+
+static const MemoryRegionOps efuse_cache_ops = {
+    .read = efuse_cache_read,
+    .write = efuse_cache_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4,
+    },
+};
+
+static void efuse_cache_init(Object *obj)
+{
+    XlnxVersalEFuseCache *s = XLNX_VERSAL_EFUSE_CACHE(obj);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+
+    memory_region_init_io(&s->iomem, obj, &efuse_cache_ops, s,
+                          TYPE_XLNX_VERSAL_EFUSE_CACHE, MR_SIZE);
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static Property efuse_cache_props[] = {
+    DEFINE_PROP_LINK("efuse",
+                     XlnxVersalEFuseCache, efuse,
+                     TYPE_XLNX_EFUSE, XlnxEFuse *),
+
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void efuse_cache_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    device_class_set_props(dc, efuse_cache_props);
+}
+
+static const TypeInfo efuse_cache_info = {
+    .name          = TYPE_XLNX_VERSAL_EFUSE_CACHE,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(XlnxVersalEFuseCache),
+    .class_init    = efuse_cache_class_init,
+    .instance_init = efuse_cache_init,
+};
+
+static void efuse_cache_register_types(void)
+{
+    type_register_static(&efuse_cache_info);
+}
+
+type_init(efuse_cache_register_types)

include/hw/nvram/xlnx-versal-efuse.h

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2020 Xilinx 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_EFUSE_H
+#define XLNX_VERSAL_EFUSE_H
+
+#include "hw/irq.h"
+#include "hw/sysbus.h"
+#include "hw/register.h"
+#include "hw/nvram/xlnx-efuse.h"
+
+#define XLNX_VERSAL_EFUSE_CTRL_R_MAX ((0x100 / 4) + 1)
+
+#define TYPE_XLNX_VERSAL_EFUSE_CTRL  "xlnx,versal-efuse"
+#define TYPE_XLNX_VERSAL_EFUSE_CACHE "xlnx,pmc-efuse-cache"
+
+OBJECT_DECLARE_SIMPLE_TYPE(XlnxVersalEFuseCtrl, XLNX_VERSAL_EFUSE_CTRL);
+OBJECT_DECLARE_SIMPLE_TYPE(XlnxVersalEFuseCache, XLNX_VERSAL_EFUSE_CACHE);
+
+struct XlnxVersalEFuseCtrl {
+    SysBusDevice parent_obj;
+    qemu_irq irq_efuse_imr;
+
+    XlnxEFuse *efuse;
+
+    void *extra_pg0_lock_spec;      /* Opaque property */
+    uint32_t extra_pg0_lock_n16;
+
+    uint32_t regs[XLNX_VERSAL_EFUSE_CTRL_R_MAX];
+    RegisterInfo regs_info[XLNX_VERSAL_EFUSE_CTRL_R_MAX];
+};
+
+struct XlnxVersalEFuseCache {
+    SysBusDevice parent_obj;
+    MemoryRegion iomem;
+
+    XlnxEFuse *efuse;
+};
+
+/**
+ * xlnx_versal_efuse_read_row:
+ * @s: the efuse object
+ * @bit: the bit-address within the 32-bit row to be read
+ * @denied: if non-NULL, to receive true if the row is write-only
+ *
+ * Returns: the 32-bit word containing address @bit; 0 if @denies is true
+ */
+uint32_t xlnx_versal_efuse_read_row(XlnxEFuse *s, uint32_t bit, bool *denied);
+
+#endif