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author | Tong Ho <tong.ho@xilinx.com> | 2021-09-16 22:23:55 -0700 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2021-09-30 13:42:10 +0100 |
commit | 461a6a6f199944e466ddb808516e63cf064c0105 (patch) | |
tree | b8fe771272f6028ee011d4e5cdee5dab04769747 /hw/nvram | |
parent | 67fa02f89fbf7510b70080bbbea8ac0aa752e8ba (diff) | |
download | qemu-461a6a6f199944e466ddb808516e63cf064c0105.zip qemu-461a6a6f199944e466ddb808516e63cf064c0105.tar.gz qemu-461a6a6f199944e466ddb808516e63cf064c0105.tar.bz2 |
hw/nvram: Introduce Xilinx battery-backed ram
This device is present in Versal and ZynqMP product
families to store a 256-bit encryption key.
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: 20210917052400.1249094-5-tong.ho@xilinx.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw/nvram')
-rw-r--r-- | hw/nvram/Kconfig | 4 | ||||
-rw-r--r-- | hw/nvram/meson.build | 1 | ||||
-rw-r--r-- | hw/nvram/xlnx-bbram.c | 545 |
3 files changed, 550 insertions, 0 deletions
diff --git a/hw/nvram/Kconfig b/hw/nvram/Kconfig index 3059c5d..24cfc18 100644 --- a/hw/nvram/Kconfig +++ b/hw/nvram/Kconfig @@ -30,3 +30,7 @@ config XLNX_EFUSE_VERSAL config XLNX_EFUSE_ZYNQMP bool select XLNX_EFUSE + +config XLNX_BBRAM + bool + select XLNX_EFUSE_CRC diff --git a/hw/nvram/meson.build b/hw/nvram/meson.build index 6dc54d9..202a546 100644 --- a/hw/nvram/meson.build +++ b/hw/nvram/meson.build @@ -16,5 +16,6 @@ softmmu_ss.add(when: 'CONFIG_XLNX_EFUSE_VERSAL', if_true: files( 'xlnx-versal-efuse-ctrl.c')) softmmu_ss.add(when: 'CONFIG_XLNX_EFUSE_ZYNQMP', if_true: files( 'xlnx-zynqmp-efuse.c')) +softmmu_ss.add(when: 'CONFIG_XLNX_BBRAM', if_true: files('xlnx-bbram.c')) specific_ss.add(when: 'CONFIG_PSERIES', if_true: files('spapr_nvram.c')) diff --git a/hw/nvram/xlnx-bbram.c b/hw/nvram/xlnx-bbram.c new file mode 100644 index 0000000..b70828e --- /dev/null +++ b/hw/nvram/xlnx-bbram.c @@ -0,0 +1,545 @@ +/* + * QEMU model of the Xilinx BBRAM Battery Backed RAM + * + * Copyright (c) 2014-2021 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-bbram.h" + +#include "qemu/error-report.h" +#include "qemu/log.h" +#include "qapi/error.h" +#include "sysemu/blockdev.h" +#include "migration/vmstate.h" +#include "hw/qdev-properties.h" +#include "hw/qdev-properties-system.h" +#include "hw/nvram/xlnx-efuse.h" + +#ifndef XLNX_BBRAM_ERR_DEBUG +#define XLNX_BBRAM_ERR_DEBUG 0 +#endif + +REG32(BBRAM_STATUS, 0x0) + FIELD(BBRAM_STATUS, AES_CRC_PASS, 9, 1) + FIELD(BBRAM_STATUS, AES_CRC_DONE, 8, 1) + FIELD(BBRAM_STATUS, BBRAM_ZEROIZED, 4, 1) + FIELD(BBRAM_STATUS, PGM_MODE, 0, 1) +REG32(BBRAM_CTRL, 0x4) + FIELD(BBRAM_CTRL, ZEROIZE, 0, 1) +REG32(PGM_MODE, 0x8) +REG32(BBRAM_AES_CRC, 0xc) +REG32(BBRAM_0, 0x10) +REG32(BBRAM_1, 0x14) +REG32(BBRAM_2, 0x18) +REG32(BBRAM_3, 0x1c) +REG32(BBRAM_4, 0x20) +REG32(BBRAM_5, 0x24) +REG32(BBRAM_6, 0x28) +REG32(BBRAM_7, 0x2c) +REG32(BBRAM_8, 0x30) +REG32(BBRAM_SLVERR, 0x34) + FIELD(BBRAM_SLVERR, ENABLE, 0, 1) +REG32(BBRAM_ISR, 0x38) + FIELD(BBRAM_ISR, APB_SLVERR, 0, 1) +REG32(BBRAM_IMR, 0x3c) + FIELD(BBRAM_IMR, APB_SLVERR, 0, 1) +REG32(BBRAM_IER, 0x40) + FIELD(BBRAM_IER, APB_SLVERR, 0, 1) +REG32(BBRAM_IDR, 0x44) + FIELD(BBRAM_IDR, APB_SLVERR, 0, 1) +REG32(BBRAM_MSW_LOCK, 0x4c) + FIELD(BBRAM_MSW_LOCK, VAL, 0, 1) + +#define R_MAX (R_BBRAM_MSW_LOCK + 1) + +#define RAM_MAX (A_BBRAM_8 + 4 - A_BBRAM_0) + +#define BBRAM_PGM_MAGIC 0x757bdf0d + +QEMU_BUILD_BUG_ON(R_MAX != ARRAY_SIZE(((XlnxBBRam *)0)->regs)); + +static bool bbram_msw_locked(XlnxBBRam *s) +{ + return ARRAY_FIELD_EX32(s->regs, BBRAM_MSW_LOCK, VAL) != 0; +} + +static bool bbram_pgm_enabled(XlnxBBRam *s) +{ + return ARRAY_FIELD_EX32(s->regs, BBRAM_STATUS, PGM_MODE) != 0; +} + +static void bbram_bdrv_error(XlnxBBRam *s, int rc, gchar *detail) +{ + Error *errp; + + error_setg_errno(&errp, -rc, "%s: BBRAM backstore %s failed.", + blk_name(s->blk), detail); + error_report("%s", error_get_pretty(errp)); + error_free(errp); + + g_free(detail); +} + +static void bbram_bdrv_read(XlnxBBRam *s, Error **errp) +{ + uint32_t *ram = &s->regs[R_BBRAM_0]; + int nr = RAM_MAX; + + if (!s->blk) { + return; + } + + s->blk_ro = !blk_supports_write_perm(s->blk); + if (!s->blk_ro) { + int rc; + + rc = blk_set_perm(s->blk, + (BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE), + BLK_PERM_ALL, NULL); + if (rc) { + s->blk_ro = true; + } + } + if (s->blk_ro) { + warn_report("%s: Skip saving updates to read-only BBRAM backstore.", + blk_name(s->blk)); + } + + if (blk_pread(s->blk, 0, ram, nr) < 0) { + error_setg(errp, + "%s: Failed to read %u bytes from BBRAM backstore.", + blk_name(s->blk), nr); + return; + } + + /* Convert from little-endian backstore for each 32-bit word */ + nr /= 4; + while (nr--) { + ram[nr] = le32_to_cpu(ram[nr]); + } +} + +static void bbram_bdrv_sync(XlnxBBRam *s, uint64_t hwaddr) +{ + uint32_t le32; + unsigned offset; + int rc; + + assert(A_BBRAM_0 <= hwaddr && hwaddr <= A_BBRAM_8); + + /* Backstore is always in little-endian */ + le32 = cpu_to_le32(s->regs[hwaddr / 4]); + + /* Update zeroized flag */ + if (le32 && (hwaddr != A_BBRAM_8 || s->bbram8_wo)) { + ARRAY_FIELD_DP32(s->regs, BBRAM_STATUS, BBRAM_ZEROIZED, 0); + } + + if (!s->blk || s->blk_ro) { + return; + } + + offset = hwaddr - A_BBRAM_0; + rc = blk_pwrite(s->blk, offset, &le32, 4, 0); + if (rc < 0) { + bbram_bdrv_error(s, rc, g_strdup_printf("write to offset %u", offset)); + } +} + +static void bbram_bdrv_zero(XlnxBBRam *s) +{ + int rc; + + ARRAY_FIELD_DP32(s->regs, BBRAM_STATUS, BBRAM_ZEROIZED, 1); + + if (!s->blk || s->blk_ro) { + return; + } + + rc = blk_make_zero(s->blk, 0); + if (rc < 0) { + bbram_bdrv_error(s, rc, g_strdup("zeroizing")); + } + + /* Restore bbram8 if it is non-zero */ + if (s->regs[R_BBRAM_8]) { + bbram_bdrv_sync(s, A_BBRAM_8); + } +} + +static void bbram_zeroize(XlnxBBRam *s) +{ + int nr = RAM_MAX - (s->bbram8_wo ? 0 : 4); /* only wo bbram8 is cleared */ + + memset(&s->regs[R_BBRAM_0], 0, nr); + bbram_bdrv_zero(s); +} + +static void bbram_update_irq(XlnxBBRam *s) +{ + bool pending = s->regs[R_BBRAM_ISR] & ~s->regs[R_BBRAM_IMR]; + + qemu_set_irq(s->irq_bbram, pending); +} + +static void bbram_ctrl_postw(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + uint32_t val = val64; + + if (val & R_BBRAM_CTRL_ZEROIZE_MASK) { + bbram_zeroize(s); + /* The bit is self clearing */ + s->regs[R_BBRAM_CTRL] &= ~R_BBRAM_CTRL_ZEROIZE_MASK; + } +} + +static void bbram_pgm_mode_postw(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + uint32_t val = val64; + + if (val == BBRAM_PGM_MAGIC) { + bbram_zeroize(s); + + /* The status bit is cleared only by POR */ + ARRAY_FIELD_DP32(s->regs, BBRAM_STATUS, PGM_MODE, 1); + } +} + +static void bbram_aes_crc_postw(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + uint32_t calc_crc; + + if (!bbram_pgm_enabled(s)) { + /* We are not in programming mode, don't do anything */ + return; + } + + /* Perform the AES integrity check */ + s->regs[R_BBRAM_STATUS] |= R_BBRAM_STATUS_AES_CRC_DONE_MASK; + + /* + * Set check status. + * + * ZynqMP BBRAM check has a zero-u32 prepended; see: + * https://github.com/Xilinx/embeddedsw/blob/release-2019.2/lib/sw_services/xilskey/src/xilskey_bbramps_zynqmp.c#L311 + */ + calc_crc = xlnx_efuse_calc_crc(&s->regs[R_BBRAM_0], + (R_BBRAM_8 - R_BBRAM_0), s->crc_zpads); + + ARRAY_FIELD_DP32(s->regs, BBRAM_STATUS, AES_CRC_PASS, + (s->regs[R_BBRAM_AES_CRC] == calc_crc)); +} + +static uint64_t bbram_key_prew(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + uint32_t original_data = *(uint32_t *) reg->data; + + if (bbram_pgm_enabled(s)) { + return val64; + } else { + /* We are not in programming mode, don't do anything */ + qemu_log_mask(LOG_GUEST_ERROR, + "Not in programming mode, dropping the write\n"); + return original_data; + } +} + +static void bbram_key_postw(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + + bbram_bdrv_sync(s, reg->access->addr); +} + +static uint64_t bbram_wo_postr(RegisterInfo *reg, uint64_t val) +{ + return 0; +} + +static uint64_t bbram_r8_postr(RegisterInfo *reg, uint64_t val) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + + return s->bbram8_wo ? bbram_wo_postr(reg, val) : val; +} + +static bool bbram_r8_readonly(XlnxBBRam *s) +{ + return !bbram_pgm_enabled(s) || bbram_msw_locked(s); +} + +static uint64_t bbram_r8_prew(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + + if (bbram_r8_readonly(s)) { + val64 = *(uint32_t *)reg->data; + } + + return val64; +} + +static void bbram_r8_postw(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + + if (!bbram_r8_readonly(s)) { + bbram_bdrv_sync(s, A_BBRAM_8); + } +} + +static uint64_t bbram_msw_lock_prew(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + + /* Never lock if bbram8 is wo; and, only POR can clear the lock */ + if (s->bbram8_wo) { + val64 = 0; + } else { + val64 |= s->regs[R_BBRAM_MSW_LOCK]; + } + + return val64; +} + +static void bbram_isr_postw(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + + bbram_update_irq(s); +} + +static uint64_t bbram_ier_prew(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + uint32_t val = val64; + + s->regs[R_BBRAM_IMR] &= ~val; + bbram_update_irq(s); + return 0; +} + +static uint64_t bbram_idr_prew(RegisterInfo *reg, uint64_t val64) +{ + XlnxBBRam *s = XLNX_BBRAM(reg->opaque); + uint32_t val = val64; + + s->regs[R_BBRAM_IMR] |= val; + bbram_update_irq(s); + return 0; +} + +static RegisterAccessInfo bbram_ctrl_regs_info[] = { + { .name = "BBRAM_STATUS", .addr = A_BBRAM_STATUS, + .rsvd = 0xee, + .ro = 0x3ff, + },{ .name = "BBRAM_CTRL", .addr = A_BBRAM_CTRL, + .post_write = bbram_ctrl_postw, + },{ .name = "PGM_MODE", .addr = A_PGM_MODE, + .post_write = bbram_pgm_mode_postw, + },{ .name = "BBRAM_AES_CRC", .addr = A_BBRAM_AES_CRC, + .post_write = bbram_aes_crc_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_0", .addr = A_BBRAM_0, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_1", .addr = A_BBRAM_1, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_2", .addr = A_BBRAM_2, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_3", .addr = A_BBRAM_3, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_4", .addr = A_BBRAM_4, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_5", .addr = A_BBRAM_5, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_6", .addr = A_BBRAM_6, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_7", .addr = A_BBRAM_7, + .pre_write = bbram_key_prew, + .post_write = bbram_key_postw, + .post_read = bbram_wo_postr, + },{ .name = "BBRAM_8", .addr = A_BBRAM_8, + .pre_write = bbram_r8_prew, + .post_write = bbram_r8_postw, + .post_read = bbram_r8_postr, + },{ .name = "BBRAM_SLVERR", .addr = A_BBRAM_SLVERR, + .rsvd = ~1, + },{ .name = "BBRAM_ISR", .addr = A_BBRAM_ISR, + .w1c = 0x1, + .post_write = bbram_isr_postw, + },{ .name = "BBRAM_IMR", .addr = A_BBRAM_IMR, + .ro = 0x1, + },{ .name = "BBRAM_IER", .addr = A_BBRAM_IER, + .pre_write = bbram_ier_prew, + },{ .name = "BBRAM_IDR", .addr = A_BBRAM_IDR, + .pre_write = bbram_idr_prew, + },{ .name = "BBRAM_MSW_LOCK", .addr = A_BBRAM_MSW_LOCK, + .pre_write = bbram_msw_lock_prew, + .ro = ~R_BBRAM_MSW_LOCK_VAL_MASK, + } +}; + +static void bbram_ctrl_reset(DeviceState *dev) +{ + XlnxBBRam *s = XLNX_BBRAM(dev); + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(s->regs_info); ++i) { + if (i < R_BBRAM_0 || i > R_BBRAM_8) { + register_reset(&s->regs_info[i]); + } + } + + bbram_update_irq(s); +} + +static const MemoryRegionOps bbram_ctrl_ops = { + .read = register_read_memory, + .write = register_write_memory, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + }, +}; + +static void bbram_ctrl_realize(DeviceState *dev, Error **errp) +{ + XlnxBBRam *s = XLNX_BBRAM(dev); + + if (s->crc_zpads) { + s->bbram8_wo = true; + } + + bbram_bdrv_read(s, errp); +} + +static void bbram_ctrl_init(Object *obj) +{ + XlnxBBRam *s = XLNX_BBRAM(obj); + SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + RegisterInfoArray *reg_array; + + reg_array = + register_init_block32(DEVICE(obj), bbram_ctrl_regs_info, + ARRAY_SIZE(bbram_ctrl_regs_info), + s->regs_info, s->regs, + &bbram_ctrl_ops, + XLNX_BBRAM_ERR_DEBUG, + R_MAX * 4); + + sysbus_init_mmio(sbd, ®_array->mem); + sysbus_init_irq(sbd, &s->irq_bbram); +} + +static void bbram_prop_set_drive(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + DeviceState *dev = DEVICE(obj); + + qdev_prop_drive.set(obj, v, name, opaque, errp); + + /* Fill initial data if backend is attached after realized */ + if (dev->realized) { + bbram_bdrv_read(XLNX_BBRAM(obj), errp); + } +} + +static void bbram_prop_get_drive(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + qdev_prop_drive.get(obj, v, name, opaque, errp); +} + +static void bbram_prop_release_drive(Object *obj, const char *name, + void *opaque) +{ + qdev_prop_drive.release(obj, name, opaque); +} + +static const PropertyInfo bbram_prop_drive = { + .name = "str", + .description = "Node name or ID of a block device to use as BBRAM backend", + .realized_set_allowed = true, + .get = bbram_prop_get_drive, + .set = bbram_prop_set_drive, + .release = bbram_prop_release_drive, +}; + +static const VMStateDescription vmstate_bbram_ctrl = { + .name = TYPE_XLNX_BBRAM, + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32_ARRAY(regs, XlnxBBRam, R_MAX), + VMSTATE_END_OF_LIST(), + } +}; + +static Property bbram_ctrl_props[] = { + DEFINE_PROP("drive", XlnxBBRam, blk, bbram_prop_drive, BlockBackend *), + DEFINE_PROP_UINT32("crc-zpads", XlnxBBRam, crc_zpads, 1), + DEFINE_PROP_END_OF_LIST(), +}; + +static void bbram_ctrl_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->reset = bbram_ctrl_reset; + dc->realize = bbram_ctrl_realize; + dc->vmsd = &vmstate_bbram_ctrl; + device_class_set_props(dc, bbram_ctrl_props); +} + +static const TypeInfo bbram_ctrl_info = { + .name = TYPE_XLNX_BBRAM, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(XlnxBBRam), + .class_init = bbram_ctrl_class_init, + .instance_init = bbram_ctrl_init, +}; + +static void bbram_ctrl_register_types(void) +{ + type_register_static(&bbram_ctrl_info); +} + +type_init(bbram_ctrl_register_types) |