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Re: [Qemu-devel] [PATCH V14 2/7] Add TPM (frontend) hardware interface (
From: |
Michael S. Tsirkin |
Subject: |
Re: [Qemu-devel] [PATCH V14 2/7] Add TPM (frontend) hardware interface (TPM TIS) to Qemu |
Date: |
Mon, 20 Feb 2012 10:51:51 +0200 |
User-agent: |
Mutt/1.5.21 (2010-09-15) |
On Wed, Dec 14, 2011 at 08:43:17AM -0500, Stefan Berger wrote:
> This patch adds the main code of the TPM frontend driver, the TPM TIS
> interface, to Qemu. The code is largely based on the previous implementation
> for Xen but has been significantly extended to meet the standard's
> requirements, such as the support for changing of localities and all the
> functionality of the available flags.
>
> Communication with the backend (i.e., for Xen or the libtpms-based one)
> is cleanly separated through an interface which the backend driver needs
> to implement.
>
> The TPM TIS driver's backend was previously chosen in the code added
> to arch_init. The frontend holds a pointer to the chosen backend (interface).
>
> Communication with the backend is largely based on signals and conditions.
> Whenever the frontend has collected a complete packet, it will signal
> the backend, which then starts processing the command. Once the result
> has been returned, the backend invokes a callback function
> (tis_tpm_receive_cb()).
>
> The one tricky part is support for VM suspend while the TPM is processing
> a command. In this case the frontend driver is waiting for the backend
> to return the result of the last command before shutting down. It waits
> on a condition for a signal from the backend, which is delivered in
> tis_tpm_receive_cb().
>
> Testing the proper functioning of the different flags and localities
> cannot be done from user space when running in Linux for example, since
> access to the address space of the TPM TIS interface is not possible. Also
> the Linux driver itself does not exercise all functionality. So, for
> testing there is a fairly extensive test suite as part of the SeaBIOS patches
> since from within the BIOS one can have full access to all the TPM's
> registers.
>
>
> Signed-off-by: Stefan Berger <address@hidden>
looks good overall
some questions on erro handling and behaviour with
a malicious guest, below.
> ---
> hw/tpm_tis.c | 807
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 807 insertions(+), 0 deletions(-)
> create mode 100644 hw/tpm_tis.c
>
> diff --git a/hw/tpm_tis.c b/hw/tpm_tis.c
> new file mode 100644
> index 0000000..bcbc987
> --- /dev/null
> +++ b/hw/tpm_tis.c
> @@ -0,0 +1,807 @@
> +/*
> + * tpm_tis.c - QEMU's TPM TIS interface emulator
> + *
> + * Copyright (C) 2006,2010,2011 IBM Corporation
> + *
> + * Authors:
> + * Stefan Berger <address@hidden>
> + * David Safford <address@hidden>
> + *
> + * Xen 4 support: Andrease Niederl <address@hidden>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation, version 2 of the
> + * License.
> + *
> + *
> + * Implementation of the TIS interface according to specs found at
> + * http://www.trustedcomputiggroup.org.
> + * In the developers menu choose the PC Client section then find the TIS
> + * specification.
> + */
> +
> +#include "tpm.h"
> +#include "block.h"
> +#include "exec-memory.h"
> +#include "hw/hw.h"
> +#include "hw/pc.h"
> +#include "hw/tpm_tis.h"
> +#include "qemu-error.h"
> +#include "qemu-common.h"
> +
> +/*#define DEBUG_TIS */
> +
> +#ifdef DEBUG_TIS
> +#define dprintf(fmt, ...) \
> + do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
> +#else
> +#define dprintf(fmt, ...) \
> + do { } while (0)
> +#endif
> +
> +/* whether the STS interrupt is supported */
> +/*#define RAISE_STS_IRQ */
> +
> +/* tis registers */
> +#define TPM_TIS_REG_ACCESS 0x00
> +#define TPM_TIS_REG_INT_ENABLE 0x08
> +#define TPM_TIS_REG_INT_VECTOR 0x0c
> +#define TPM_TIS_REG_INT_STATUS 0x10
> +#define TPM_TIS_REG_INTF_CAPABILITY 0x14
> +#define TPM_TIS_REG_STS 0x18
> +#define TPM_TIS_REG_DATA_FIFO 0x24
> +#define TPM_TIS_REG_DID_VID 0xf00
> +#define TPM_TIS_REG_RID 0xf04
> +
> +#define TPM_TIS_STS_VALID (1 << 7)
> +#define TPM_TIS_STS_COMMAND_READY (1 << 6)
> +#define TPM_TIS_STS_TPM_GO (1 << 5)
> +#define TPM_TIS_STS_DATA_AVAILABLE (1 << 4)
> +#define TPM_TIS_STS_EXPECT (1 << 3)
> +#define TPM_TIS_STS_RESPONSE_RETRY (1 << 1)
> +
> +#define TPM_TIS_ACCESS_TPM_REG_VALID_STS (1 << 7)
> +#define TPM_TIS_ACCESS_ACTIVE_LOCALITY (1 << 5)
> +#define TPM_TIS_ACCESS_BEEN_SEIZED (1 << 4)
> +#define TPM_TIS_ACCESS_SEIZE (1 << 3)
> +#define TPM_TIS_ACCESS_PENDING_REQUEST (1 << 2)
> +#define TPM_TIS_ACCESS_REQUEST_USE (1 << 1)
> +#define TPM_TIS_ACCESS_TPM_ESTABLISHMENT (1 << 0)
> +
> +#define TPM_TIS_INT_ENABLED (1 << 31)
> +#define TPM_TIS_INT_DATA_AVAILABLE (1 << 0)
> +#define TPM_TIS_INT_STS_VALID (1 << 1)
> +#define TPM_TIS_INT_LOCALITY_CHANGED (1 << 2)
> +#define TPM_TIS_INT_COMMAND_READY (1 << 7)
> +
> +#ifndef RAISE_STS_IRQ
> +
> +# define TPM_TIS_INTERRUPTS_SUPPORTED (TPM_TIS_INT_LOCALITY_CHANGED | \
> + TPM_TIS_INT_DATA_AVAILABLE | \
> + TPM_TIS_INT_COMMAND_READY)
> +
> +#else
> +
> +# define TPM_TIS_INTERRUPTS_SUPPORTED (TPM_TIS_INT_LOCALITY_CHANGED | \
> + TPM_TIS_INT_DATA_AVAILABLE | \
> + TPM_TIS_INT_STS_VALID | \
> + TPM_TIS_INT_COMMAND_READY)
> +
let's keep these as #define
> +#endif
> +
> +#define TPM_TIS_CAPABILITIES_SUPPORTED ((1 << 4) | \
> + TPM_TIS_INTERRUPTS_SUPPORTED)
> +
> +#define TPM_TIS_TPM_DID 0x0001
> +#define TPM_TIS_TPM_VID 0x0001
> +#define TPM_TIS_TPM_RID 0x0001
> +
> +#define TPM_TIS_NO_DATA_BYTE 0xff
> +
> +/* utility functions */
> +
> +static uint8_t tpm_tis_locality_from_addr(target_phys_addr_t addr)
> +{
> + return (uint8_t)((addr >> 12) & 0x7);
> +}
> +
note this can give a number 0..6
> +static uint32_t tpm_tis_get_size_from_buffer(const TPMSizedBuffer *sb)
> +{
> + return be32_to_cpu(*(uint32_t *)&sb->buffer[2]);
> +}
> +
> +static void tpm_tis_show_buffer(const TPMSizedBuffer *sb, const char *string)
> +{
> +#ifdef DEBUG_TIS
> + uint32_t len, i;
> +
> + len = tpm_tis_get_size_from_buffer(sb);
> + dprintf("tpm_tis: %s length = %d\n", string, len);
> + for (i = 0; i < len; i++) {
> + if (i && !(i & 16)) {
> + dprintf("\n");
> + }
> + dprintf("%.2X ", sb->buffer[i]);
> + }
> + dprintf("\n");
> +#endif
> +}
> +
> +
> +/*
> + * Send a TPM request.
> + * Call this with the state_lock held so we can sync with the receive
> + * callback.
> + */
> +static void tpm_tis_tpm_send(TPMState *s, uint8_t locty)
> +{
> + TPMTISState *tis = &s->s.tis;
> +
> + tpm_tis_show_buffer(&tis->loc[locty].w_buffer, "tpm_tis: To TPM");
> +
> + s->command_locty = locty;
> + s->cmd_locty = &tis->loc[locty];
> +
> + /* w_offset serves as length indicator for length of data;
> + it's reset when the response comes back */
> + tis->loc[locty].status = TPM_TIS_STATUS_EXECUTION;
> + tis->loc[locty].sts &= ~TPM_TIS_STS_EXPECT;
> +
> + s->to_tpm_execute = true;
> + qemu_cond_signal(&s->to_tpm_cond);
> +}
> +
> +/* raise an interrupt if allowed */
> +static void tpm_tis_raise_irq(TPMState *s, uint8_t locty, uint32_t irqmask)
> +{
> + TPMTISState *tis = &s->s.tis;
> +
> + if (!TPM_TIS_IS_VALID_LOCTY(locty)) {
> + return;
> + }
> +
> + if ((tis->loc[locty].inte & TPM_TIS_INT_ENABLED) &&
> + (tis->loc[locty].inte & irqmask)) {
> + dprintf("tpm_tis: Raising IRQ for flag %08x\n", irqmask);
> + qemu_irq_raise(s->s.tis.irq);
> + tis->loc[locty].ints |= irqmask;
> + }
> +}
> +
> +static uint32_t tpm_tis_check_request_use_except(TPMState *s, uint8_t locty)
> +{
> + uint8_t l;
> +
> + for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) {
> + if (l == locty) {
> + continue;
> + }
> + if ((s->s.tis.loc[l].access & TPM_TIS_ACCESS_REQUEST_USE)) {
> + return 1;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void tpm_tis_new_active_locality(TPMState *s, uint8_t
> new_active_locty)
> +{
> + TPMTISState *tis = &s->s.tis;
> + int change = (s->s.tis.active_locty != new_active_locty);
> +
> + if (change && TPM_TIS_IS_VALID_LOCTY(s->s.tis.active_locty)) {
> + /* reset flags on the old active locality */
> + tis->loc[s->s.tis.active_locty].access &=
> +
> ~(TPM_TIS_ACCESS_ACTIVE_LOCALITY|TPM_TIS_ACCESS_REQUEST_USE);
> + if (TPM_TIS_IS_VALID_LOCTY(new_active_locty) &&
> + tis->loc[new_active_locty].access & TPM_TIS_ACCESS_SEIZE) {
> + tis->loc[tis->active_locty].access |= TPM_TIS_ACCESS_BEEN_SEIZED;
> + }
> + }
> +
> + tis->active_locty = new_active_locty;
should this happen with invalid locality?
> +
> + dprintf("tpm_tis: Active locality is now %d\n", s->s.tis.active_locty);
> +
> + if (TPM_TIS_IS_VALID_LOCTY(new_active_locty)) {
> + /* set flags on the new active locality */
> + tis->loc[new_active_locty].access |= TPM_TIS_ACCESS_ACTIVE_LOCALITY;
> + tis->loc[new_active_locty].access &= ~(TPM_TIS_ACCESS_REQUEST_USE |
> + TPM_TIS_ACCESS_SEIZE);
> + }
> +
> + if (change) {
> + tpm_tis_raise_irq(s, tis->active_locty,
> TPM_TIS_INT_LOCALITY_CHANGED);
> + }
> +}
> +
> +/* abort -- this function switches the locality */
> +static void tpm_tis_abort(TPMState *s, uint8_t locty)
> +{
> + TPMTISState *tis = &s->s.tis;
> +
> + tis->loc[locty].r_offset = 0;
> + tis->loc[locty].w_offset = 0;
> +
> + dprintf("tpm_tis: tis_abort: new active locality is %d\n",
> tis->next_locty);
> +
> + /*
> + * Need to react differently depending on who's aborting now and
> + * which locality will become active afterwards.
> + */
> + if (tis->aborting_locty == tis->next_locty) {
> + tis->loc[tis->aborting_locty].status = TPM_TIS_STATUS_READY;
> + tis->loc[tis->aborting_locty].sts = TPM_TIS_STS_COMMAND_READY;
> + tpm_tis_raise_irq(s, tis->aborting_locty, TPM_TIS_INT_COMMAND_READY);
> + }
> +
> + /* locality after abort is another one than the current one */
> + tpm_tis_new_active_locality(s, tis->next_locty);
> +
> + tis->next_locty = TPM_TIS_NO_LOCALITY;
> + /* nobody's aborting a command anymore */
> + tis->aborting_locty = TPM_TIS_NO_LOCALITY;
> +}
> +
> +/* prepare aborting current command */
> +static void tpm_tis_prep_abort(TPMState *s, uint8_t locty, uint8_t newlocty)
> +{
> + TPMTISState *tis = &s->s.tis;
> + uint8_t busy_locty;
> +
> + tis->aborting_locty = locty;
> + tis->next_locty = newlocty; /* locality after successful abort */
> +
> + /*
> + * only abort a command using an interrupt if currently executing
> + * a command AND if there's a valid connection to the vTPM.
> + */
> + for (busy_locty = 0; busy_locty < TPM_TIS_NUM_LOCALITIES; busy_locty++) {
> + if (tis->loc[busy_locty].status == TPM_TIS_STATUS_EXECUTION) {
> + /* there is currently no way to interrupt the TPM's operations
> + while it's executing a command; once the TPM is done and
> + returns the buffer, it will switch to the next_locty; */
> + dprintf("tpm_tis: Locality %d is busy - deferring abort\n",
> + busy_locty);
> + return;
> + }
> + }
> +
> + tpm_tis_abort(s, locty);
> +}
> +
> +/*
> + * Callback from the TPM to indicate that the response was received.
> + */
> +static void tpm_tis_receive_cb(TPMState *s, uint8_t locty)
> +{
> + TPMTISState *tis = &s->s.tis;
> +
> + qemu_mutex_lock(&s->state_lock);
> +
> + tis->loc[locty].sts = TPM_TIS_STS_VALID | TPM_TIS_STS_DATA_AVAILABLE;
> + tis->loc[locty].status = TPM_TIS_STATUS_COMPLETION;
> + tis->loc[locty].r_offset = 0;
> + tis->loc[locty].w_offset = 0;
> +
> + if (TPM_TIS_IS_VALID_LOCTY(tis->next_locty)) {
> + tpm_tis_abort(s, locty);
> + }
> +
> + qemu_cond_signal(&s->from_tpm_cond);
> +
> + qemu_mutex_unlock(&s->state_lock);
> +
> +#ifndef RAISE_STS_IRQ
> + tpm_tis_raise_irq(s, locty, TPM_TIS_INT_DATA_AVAILABLE);
> +#else
> + tpm_tis_raise_irq(s, locty,
> + TPM_TIS_INT_DATA_AVAILABLE | TPM_TIS_INT_STS_VALID);
> +#endif
> +}
> +
> +/*
> + * read a byte of response data
> + * call this with s->state_lock held
> + */
> +static uint32_t tpm_tis_data_read(TPMState *s, uint8_t locty)
> +{
> + TPMTISState *tis = &s->s.tis;
> + uint32_t ret = TPM_TIS_NO_DATA_BYTE;
> + uint16_t len;
> +
> + if ((tis->loc[locty].sts & TPM_TIS_STS_DATA_AVAILABLE)) {
> + len = tpm_tis_get_size_from_buffer(&tis->loc[locty].r_buffer);
> +
> + ret = tis->loc[locty].r_buffer.buffer[tis->loc[locty].r_offset++];
what prevents this from being called when r_offset == len,
with a malicious guest?
> + if (tis->loc[locty].r_offset >= len) {
> + /* got last byte */
> + tis->loc[locty].sts = TPM_TIS_STS_VALID;
> +#ifdef RAISE_STS_IRQ
> + tpm_tis_raise_irq(s, locty, TPM_TIS_INT_STS_VALID);
> +#endif
> + }
> + dprintf("tpm_tis: tpm_tis_data_read byte 0x%02x [%d]\n",
> + ret, tis->loc[locty].r_offset-1);
> + }
> +
> + return ret;
> +}
> +
> +/*
> + * Read a register of the TIS interface
> + * See specs pages 33-63 for description of the registers
> + */
> +static uint64_t tpm_tis_mmio_read(void *opaque, target_phys_addr_t addr,
> + unsigned size)
> +{
> + TPMState *s = opaque;
> + TPMTISState *tis = &s->s.tis;
> + uint16_t offset = addr & 0xffc;
> + uint8_t shift = (addr & 0x3) * 8;
> + uint32_t val = 0xffffffff;
> + uint8_t locty = tpm_tis_locality_from_addr(addr);
Apparently locty can be 0..6 but loc array only has 5 entries.
What if a guest accesses an invalid one?
> +
> + qemu_mutex_lock(&s->state_lock);
> +
> + if (s->be_driver->ops->had_startup_error(s->be_driver)) {
> + qemu_mutex_unlock(&s->state_lock);
> + return val;
> + }
> +
> + switch (offset) {
> + case TPM_TIS_REG_ACCESS:
> + /* never show the SEIZE flag even though we use it internally */
> + val = tis->loc[locty].access & ~TPM_TIS_ACCESS_SEIZE;
> + /* the pending flag is alawys calculated */
> + if (tpm_tis_check_request_use_except(s, locty)) {
> + val |= TPM_TIS_ACCESS_PENDING_REQUEST;
> + }
> + val |= !s->be_driver->ops->get_tpm_established_flag(s->be_driver);
> + break;
> + case TPM_TIS_REG_INT_ENABLE:
> + val = tis->loc[locty].inte;
> + break;
> + case TPM_TIS_REG_INT_VECTOR:
> + val = tis->irq_num;
> + break;
> + case TPM_TIS_REG_INT_STATUS:
> + val = tis->loc[locty].ints;
> + break;
> + case TPM_TIS_REG_INTF_CAPABILITY:
> + val = TPM_TIS_CAPABILITIES_SUPPORTED;
> + break;
> + case TPM_TIS_REG_STS:
> + if (tis->active_locty == locty) {
> + if ((tis->loc[locty].sts & TPM_TIS_STS_DATA_AVAILABLE)) {
> + val =
> (tpm_tis_get_size_from_buffer(&tis->loc[locty].r_buffer)
> + - tis->loc[locty].r_offset) << 8 |
> tis->loc[locty].sts;
> + } else {
> + val = (tis->loc[locty].w_buffer.size -
> + tis->loc[locty].w_offset) << 8 | tis->loc[locty].sts;
> + }
> + }
> + break;
> + case TPM_TIS_REG_DATA_FIFO:
> + if (tis->active_locty == locty) {
> + switch (tis->loc[locty].status) {
> + case TPM_TIS_STATUS_COMPLETION:
> + val = tpm_tis_data_read(s, locty);
> + break;
> + default:
> + val = TPM_TIS_NO_DATA_BYTE;
> + break;
> + }
> + }
> + break;
> + case TPM_TIS_REG_DID_VID:
> + val = (TPM_TIS_TPM_DID << 16) | TPM_TIS_TPM_VID;
> + break;
> + case TPM_TIS_REG_RID:
> + val = TPM_TIS_TPM_RID;
> + break;
> + }
> +
> + qemu_mutex_unlock(&s->state_lock);
> +
> + if (shift) {
> + val >>= shift;
> + }
> +
> + dprintf("tpm_tis: read.%u(%08x) = %08x\n", size, (int)addr,
> (uint32_t)val);
> +
> + return val;
> +}
> +
> +/*
> + * Write a value to a register of the TIS interface
> + * See specs pages 33-63 for description of the registers
> + */
> +static void tpm_tis_mmio_write_intern(void *opaque, target_phys_addr_t addr,
> + uint64_t val, unsigned size,
> + bool hw_access)
> +{
> + TPMState *s = opaque;
> + TPMTISState *tis = &s->s.tis;
> + uint16_t off = addr & 0xfff;
> + uint8_t locty = tpm_tis_locality_from_addr(addr);
> + uint8_t active_locty, l;
> + int c, set_new_locty = 1;
> + uint16_t len;
> +
> + dprintf("tpm_tis: write.%u(%08x) = %08x\n", size, (int)addr,
> (uint32_t)val);
> +
> + qemu_mutex_lock(&s->state_lock);
> +
> + if (s->be_driver->ops->had_startup_error(s->be_driver)) {
> + qemu_mutex_unlock(&s->state_lock);
> + return;
> + }
> +
> + switch (off) {
> + case TPM_TIS_REG_ACCESS:
> +
> + if ((val & TPM_TIS_ACCESS_SEIZE)) {
> + val &= ~(TPM_TIS_ACCESS_REQUEST_USE |
> + TPM_TIS_ACCESS_ACTIVE_LOCALITY);
> + }
> +
> + active_locty = tis->active_locty;
> +
> + if ((val & TPM_TIS_ACCESS_ACTIVE_LOCALITY)) {
> + /* give up locality if currently owned */
> + if (tis->active_locty == locty) {
> + dprintf("tpm_tis: Releasing locality %d\n", locty);
> +
> + uint8_t newlocty = TPM_TIS_NO_LOCALITY;
> + /* anybody wants the locality ? */
> + for (c = TPM_TIS_NUM_LOCALITIES - 1; c >= 0; c--) {
> + if ((tis->loc[c].access & TPM_TIS_ACCESS_REQUEST_USE)) {
> + dprintf("tpm_tis: Locality %d requests use.\n", c);
> + newlocty = c;
> + break;
> + }
> + }
> + dprintf("tpm_tis: TPM_TIS_ACCESS_ACTIVE_LOCALITY: "
> + "Next active locality: %d\n",
> + newlocty);
> +
> + if (TPM_TIS_IS_VALID_LOCTY(newlocty)) {
> + set_new_locty = 0;
> + tpm_tis_prep_abort(s, locty, newlocty);
> + } else {
> + active_locty = TPM_TIS_NO_LOCALITY;
> + }
> + } else {
> + /* not currently the owner; clear a pending request */
> + tis->loc[locty].access &= ~TPM_TIS_ACCESS_REQUEST_USE;
> + }
> + }
> +
> + if ((val & TPM_TIS_ACCESS_BEEN_SEIZED)) {
> + tis->loc[locty].access &= ~TPM_TIS_ACCESS_BEEN_SEIZED;
> + }
> +
> + if ((val & TPM_TIS_ACCESS_SEIZE)) {
> + /* allow seize if a locality is active and the requesting
> + locality is higher than the one that's active
> + OR
> + allow seize for requesting locality if no locality is
> + active */
/*
* multiline comments should look like this
*/
> + while ((TPM_TIS_IS_VALID_LOCTY(tis->active_locty) &&
> + locty > tis->active_locty) ||
> + (!TPM_TIS_IS_VALID_LOCTY(tis->active_locty))) {
Clearer as:
(locty > tis->active_locty ||
!TPM_TIS_IS_VALID_LOCTY(tis->active_locty))
> +
> + /* already a pending SEIZE ? */
> + if ((tis->loc[locty].access & TPM_TIS_ACCESS_SEIZE)) {
> + break;
> + }
> +
> + /* check for ongoing seize by a higher locality */
> + for (l = locty + 1; l < TPM_TIS_NUM_LOCALITIES; l++) {
> + if ((tis->loc[l].access & TPM_TIS_ACCESS_SEIZE)) {
> + break;
> + }
> + }
> +
> + /* cancel any seize by a lower locality */
> + for (l = 0; l < locty - 1; l++) {
> + tis->loc[l].access &= ~TPM_TIS_ACCESS_SEIZE;
> + }
> +
> + tis->loc[locty].access |= TPM_TIS_ACCESS_SEIZE;
> + dprintf("tpm_tis: TPM_TIS_ACCESS_SEIZE: "
> + "Locality %d seized from locality %d\n",
> + locty, tis->active_locty);
> + dprintf("tpm_tis: TPM_TIS_ACCESS_SEIZE: Initiating
> abort.\n");
> + set_new_locty = 0;
> + tpm_tis_prep_abort(s, tis->active_locty, locty);
> + break;
> + }
> + }
> +
> + if ((val & TPM_TIS_ACCESS_REQUEST_USE)) {
> + if (tis->active_locty != locty) {
> + if (TPM_TIS_IS_VALID_LOCTY(tis->active_locty)) {
> + tis->loc[locty].access |= TPM_TIS_ACCESS_REQUEST_USE;
> + } else {
> + /* no locality active -> make this one active now */
> + active_locty = locty;
> + }
> + }
> + }
> +
> + if (set_new_locty) {
> + tpm_tis_new_active_locality(s, active_locty);
> + }
> +
> + break;
> + case TPM_TIS_REG_INT_ENABLE:
> + if (tis->active_locty != locty) {
> + break;
> + }
> +
> + tis->loc[locty].inte = (val & (TPM_TIS_INT_ENABLED | (0x3 << 3) |
> + TPM_TIS_INTERRUPTS_SUPPORTED));
> + break;
> + case TPM_TIS_REG_INT_VECTOR:
> + /* hard wired -- ignore */
> + break;
> + case TPM_TIS_REG_INT_STATUS:
> + if (tis->active_locty != locty) {
> + break;
> + }
> +
> + /* clearing of interrupt flags */
> + if (((val & TPM_TIS_INTERRUPTS_SUPPORTED)) &&
> + (tis->loc[locty].ints & TPM_TIS_INTERRUPTS_SUPPORTED)) {
> + tis->loc[locty].ints &= ~val;
> + if (tis->loc[locty].ints == 0) {
> + qemu_irq_lower(tis->irq);
> + dprintf("tpm_tis: Lowering IRQ\n");
> + }
> + }
> + tis->loc[locty].ints &= ~(val & TPM_TIS_INTERRUPTS_SUPPORTED);
> + break;
> + case TPM_TIS_REG_STS:
> + if (tis->active_locty != locty) {
> + break;
> + }
> +
> + val &= (TPM_TIS_STS_COMMAND_READY | TPM_TIS_STS_TPM_GO |
> + TPM_TIS_STS_RESPONSE_RETRY);
> +
> + if (val == TPM_TIS_STS_COMMAND_READY) {
> + switch (tis->loc[locty].status) {
> +
> + case TPM_TIS_STATUS_READY:
> + tis->loc[locty].w_offset = 0;
> + tis->loc[locty].r_offset = 0;
> + break;
> +
> + case TPM_TIS_STATUS_IDLE:
> + tis->loc[locty].sts = TPM_TIS_STS_COMMAND_READY;
> + tis->loc[locty].status = TPM_TIS_STATUS_READY;
> + tpm_tis_raise_irq(s, locty, TPM_TIS_INT_COMMAND_READY);
> + break;
> +
> + case TPM_TIS_STATUS_EXECUTION:
> + case TPM_TIS_STATUS_RECEPTION:
> + /* abort currently running command */
> + dprintf("tpm_tis: %s: Initiating abort.\n",
> + __func__);
> + tpm_tis_prep_abort(s, locty, locty);
> + break;
> +
> + case TPM_TIS_STATUS_COMPLETION:
> + tis->loc[locty].w_offset = 0;
> + tis->loc[locty].r_offset = 0;
> + /* shortcut to ready state with C/R set */
> + tis->loc[locty].status = TPM_TIS_STATUS_READY;
> + if (!(tis->loc[locty].sts & TPM_TIS_STS_COMMAND_READY)) {
> + tis->loc[locty].sts = TPM_TIS_STS_COMMAND_READY;
> + tpm_tis_raise_irq(s, locty, TPM_TIS_INT_COMMAND_READY);
> + }
> + break;
> +
> + }
> + } else if (val == TPM_TIS_STS_TPM_GO) {
> + switch (tis->loc[locty].status) {
> + case TPM_TIS_STATUS_RECEPTION:
> + tpm_tis_tpm_send(s, locty);
> + break;
> + default:
> + /* ignore */
> + break;
> + }
> + } else if (val == TPM_TIS_STS_RESPONSE_RETRY) {
> + switch (tis->loc[locty].status) {
> + case TPM_TIS_STATUS_COMPLETION:
> + tis->loc[locty].r_offset = 0;
> + tis->loc[locty].sts = TPM_TIS_STS_VALID |
> + TPM_TIS_STS_DATA_AVAILABLE;
> + break;
> + default:
> + /* ignore */
> + break;
> + }
> + }
> + break;
> + case TPM_TIS_REG_DATA_FIFO:
> + /* data fifo */
> + if (tis->active_locty != locty) {
> + break;
> + }
> +
> + if (tis->loc[locty].status == TPM_TIS_STATUS_IDLE ||
> + tis->loc[locty].status == TPM_TIS_STATUS_EXECUTION ||
> + tis->loc[locty].status == TPM_TIS_STATUS_COMPLETION) {
> + /* drop the byte */
> + } else {
> + dprintf("tpm_tis: Byte to send to TPM: %02x\n", (uint8_t)val);
> + if (tis->loc[locty].status == TPM_TIS_STATUS_READY) {
> + tis->loc[locty].status = TPM_TIS_STATUS_RECEPTION;
> + tis->loc[locty].sts = TPM_TIS_STS_EXPECT | TPM_TIS_STS_VALID;
> + }
> +
> + if ((tis->loc[locty].sts & TPM_TIS_STS_EXPECT)) {
> + if (tis->loc[locty].w_offset <
> tis->loc[locty].w_buffer.size) {
> + tis->loc[locty].w_buffer.
> + buffer[tis->loc[locty].w_offset++] = (uint8_t)val;
> + } else {
> + tis->loc[locty].sts = TPM_TIS_STS_VALID;
> + }
> + }
> +
> + /* check for complete packet */
> + if (tis->loc[locty].w_offset > 5 &&
> + (tis->loc[locty].sts & TPM_TIS_STS_EXPECT)) {
> + /* we have a packet length - see if we have all of it */
> +#ifdef RAISE_STS_IRQ
> + bool needIrq = !(tis->loc[locty].sts & TPM_TIS_STS_VALID);
> +#endif
> + len =
> tpm_tis_get_size_from_buffer(&tis->loc[locty].w_buffer);
> + if (len > tis->loc[locty].w_offset) {
> + tis->loc[locty].sts = TPM_TIS_STS_EXPECT |
> + TPM_TIS_STS_VALID;
> + } else {
> + /* packet complete */
> + tis->loc[locty].sts = TPM_TIS_STS_VALID;
> + }
> +#ifdef RAISE_STS_IRQ
> + if (needIrq) {
> + tpm_tis_raise_irq(s, locty, TPM_TIS_INT_STS_VALID);
> + }
> +#endif
> + }
> + }
> + break;
> + }
> +
> + qemu_mutex_unlock(&s->state_lock);
> +}
> +
> +static void tpm_tis_mmio_write(void *opaque, target_phys_addr_t addr,
> + uint64_t val, unsigned size)
> +{
> + return tpm_tis_mmio_write_intern(opaque, addr, val, size, false);
> +}
> +
> +static const MemoryRegionOps tpm_tis_memory_ops = {
> + .read = tpm_tis_mmio_read,
> + .write = tpm_tis_mmio_write,
> + .endianness = DEVICE_NATIVE_ENDIAN,
Are you sure? Most devices are BIG or LITTLE.
> + .valid = {
> + .min_access_size = 1,
> + .max_access_size = 4,
> + },
> +};
> +
> +static int tpm_tis_do_startup_tpm(TPMState *s)
> +{
> + return s->be_driver->ops->startup_tpm(s->be_driver);
> +}
> +
> +/*
> + * This function is called when the machine starts, resets or due to
> + * S3 resume.
> + */
> +static void tpm_tis_reset(DeviceState *d)
> +{
> + TPMState *s = container_of(d, TPMState, busdev.qdev);
> + TPMTISState *tis = &s->s.tis;
> + int c;
> +
> + s->tpm_initialized = false;
> +
> + s->be_driver->ops->reset(s->be_driver);
> +
> + tis->active_locty = TPM_TIS_NO_LOCALITY;
> + tis->next_locty = TPM_TIS_NO_LOCALITY;
> + tis->aborting_locty = TPM_TIS_NO_LOCALITY;
> +
> + for (c = 0; c < TPM_TIS_NUM_LOCALITIES; c++) {
> + tis->loc[c].access = TPM_TIS_ACCESS_TPM_REG_VALID_STS;
> + tis->loc[c].sts = 0;
> + tis->loc[c].inte = (1 << 3);
> + tis->loc[c].ints = 0;
> + tis->loc[c].status = TPM_TIS_STATUS_IDLE;
> +
> + tis->loc[c].w_offset = 0;
> + s->be_driver->ops->realloc_buffer(&tis->loc[c].w_buffer);
> + tis->loc[c].r_offset = 0;
> + s->be_driver->ops->realloc_buffer(&tis->loc[c].r_buffer);
> + }
> +
> + tpm_tis_do_startup_tpm(s);
> +}
> +
> +static int tpm_tis_init(ISADevice *dev)
> +{
> + TPMState *s = DO_UPCAST(TPMState, busdev, dev);
Let's stay consistent DO_UPCAST versus container_of.
> + TPMTISState *tis = &s->s.tis;
> + int rc;
> +
> + qemu_mutex_init(&s->state_lock);
> + qemu_cond_init(&s->from_tpm_cond);
> + qemu_cond_init(&s->to_tpm_cond);
> +
> + s->be_driver = qemu_find_tpm(s->backend);
> + if (!s->be_driver) {
> + error_report("tpm_tis: backend driver with id %s could not be "
> + "found.n\n", s->backend);
> + return -1;
goto forward to have a single exit point?
> + }
> +
> + s->be_driver->fe_model = "tpm-tis";
> +
> + if (s->be_driver->ops->init(s->be_driver, s, tpm_tis_receive_cb)) {
> + return -1;
goto forward?
> + }
> +
> + isa_init_irq(dev, &tis->irq, tis->irq_num);
probably should validate irq_num so an illegal value
gives us an error not an assert.
> +
> + memory_region_init_io(&s->mmio, &tpm_tis_memory_ops, s, "tpm-tis-mmio",
> + 0x1000 * TPM_TIS_NUM_LOCALITIES);
> + memory_region_add_subregion(get_system_memory(), TPM_TIS_ADDR_BASE,
> + &s->mmio);
> +
> + rc = tpm_tis_do_startup_tpm(s);
> + if (rc != 0) {
> + goto err_destroy_memory;
> + }
> +
> + return 0;
> +
> + err_destroy_memory:
You must delete mmio as subregion before destroy.
> + memory_region_destroy(&s->mmio);
> +
> + return -1;
> +}
> +
> +static const VMStateDescription vmstate_tpm_tis = {
> + .name = "tpm",
> + .unmigratable = 1,
I think the passthrough backend is what makes
it unmigrateable, no?
If so in the future it would be better to get that info from backend.
For now I guess we are ok as is, but pls add a comment.
> +};
> +
> +static ISADeviceInfo tpm_tis_device_info = {
> + .init = tpm_tis_init,
> + .qdev.name = "tpm-tis",
> + .qdev.size = sizeof(TPMState),
> + .qdev.vmsd = &vmstate_tpm_tis,
> + .qdev.reset = tpm_tis_reset,
> + .qdev.props = (Property[]) {
> + DEFINE_PROP_UINT32("irq", TPMState,
> + s.tis.irq_num, TPM_TIS_IRQ),
> + DEFINE_PROP_STRING("tpmdev", TPMState, backend),
> + DEFINE_PROP_END_OF_LIST(),
> + },
> +};
> +
> +static void tpm_tis_register_device(void)
> +{
> + isa_qdev_register(&tpm_tis_device_info);
So this needs to be rebased to the QOM.
Also a question: looking at the linux drivers
there's pnp support but we don't have
that yet, right? So you need to force
non-pnp mode in guest?
> +}
> +
> +device_init(tpm_tis_register_device)
> --
> 1.7.6.4
>
- Re: [Qemu-devel] [PATCH V14 2/7] Add TPM (frontend) hardware interface (TPM TIS) to Qemu,
Michael S. Tsirkin <=