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path: root/drivers/crypto/ccp/psp-dev.c
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-rw-r--r--drivers/crypto/ccp/psp-dev.c381
1 files changed, 381 insertions, 0 deletions
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
new file mode 100644
index 000000000..b14ce5106
--- /dev/null
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -0,0 +1,381 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Platform Security Processor (PSP) interface
+ *
+ * Copyright (C) 2016,2019 Advanced Micro Devices, Inc.
+ *
+ * Author: Brijesh Singh <brijesh.singh@amd.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/irqreturn.h>
+#include <linux/mutex.h>
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+
+#include "sp-dev.h"
+#include "psp-dev.h"
+#include "sev-dev.h"
+#include "tee-dev.h"
+#include "sfs.h"
+#include "platform-access.h"
+#include "dbc.h"
+#include "hsti.h"
+
+struct psp_device *psp_master;
+
+#define PSP_C2PMSG_17_CMDRESP_CMD GENMASK(19, 16)
+
+static int psp_mailbox_poll(const void __iomem *cmdresp_reg, unsigned int *cmdresp,
+ unsigned int timeout_msecs)
+{
+ while (true) {
+ *cmdresp = ioread32(cmdresp_reg);
+ if (FIELD_GET(PSP_CMDRESP_RESP, *cmdresp))
+ return 0;
+
+ if (!timeout_msecs--)
+ break;
+
+ usleep_range(1000, 1100);
+ }
+
+ return -ETIMEDOUT;
+}
+
+int psp_mailbox_command(struct psp_device *psp, enum psp_cmd cmd, void *cmdbuff,
+ unsigned int timeout_msecs, unsigned int *cmdresp)
+{
+ void __iomem *cmdresp_reg, *cmdbuff_lo_reg, *cmdbuff_hi_reg;
+ int ret;
+
+ if (!psp || !psp->vdata || !psp->vdata->cmdresp_reg ||
+ !psp->vdata->cmdbuff_addr_lo_reg || !psp->vdata->cmdbuff_addr_hi_reg)
+ return -ENODEV;
+
+ cmdresp_reg = psp->io_regs + psp->vdata->cmdresp_reg;
+ cmdbuff_lo_reg = psp->io_regs + psp->vdata->cmdbuff_addr_lo_reg;
+ cmdbuff_hi_reg = psp->io_regs + psp->vdata->cmdbuff_addr_hi_reg;
+
+ mutex_lock(&psp->mailbox_mutex);
+
+ /* Ensure mailbox is ready for a command */
+ ret = -EBUSY;
+ if (psp_mailbox_poll(cmdresp_reg, cmdresp, 0))
+ goto unlock;
+
+ if (cmdbuff) {
+ iowrite32(lower_32_bits(__psp_pa(cmdbuff)), cmdbuff_lo_reg);
+ iowrite32(upper_32_bits(__psp_pa(cmdbuff)), cmdbuff_hi_reg);
+ }
+
+ *cmdresp = FIELD_PREP(PSP_C2PMSG_17_CMDRESP_CMD, cmd);
+ iowrite32(*cmdresp, cmdresp_reg);
+
+ ret = psp_mailbox_poll(cmdresp_reg, cmdresp, timeout_msecs);
+
+unlock:
+ mutex_unlock(&psp->mailbox_mutex);
+
+ return ret;
+}
+
+int psp_extended_mailbox_cmd(struct psp_device *psp, unsigned int timeout_msecs,
+ struct psp_ext_request *req)
+{
+ unsigned int reg;
+ int ret;
+
+ print_hex_dump_debug("->psp ", DUMP_PREFIX_OFFSET, 16, 2, req,
+ req->header.payload_size, false);
+
+ ret = psp_mailbox_command(psp, PSP_CMD_TEE_EXTENDED_CMD, (void *)req,
+ timeout_msecs, &reg);
+ if (ret) {
+ return ret;
+ } else if (FIELD_GET(PSP_CMDRESP_STS, reg)) {
+ req->header.status = FIELD_GET(PSP_CMDRESP_STS, reg);
+ return -EIO;
+ }
+
+ print_hex_dump_debug("<-psp ", DUMP_PREFIX_OFFSET, 16, 2, req,
+ req->header.payload_size, false);
+
+ return 0;
+}
+
+static struct psp_device *psp_alloc_struct(struct sp_device *sp)
+{
+ struct device *dev = sp->dev;
+ struct psp_device *psp;
+
+ psp = devm_kzalloc(dev, sizeof(*psp), GFP_KERNEL);
+ if (!psp)
+ return NULL;
+
+ psp->dev = dev;
+ psp->sp = sp;
+
+ snprintf(psp->name, sizeof(psp->name), "psp-%u", sp->ord);
+
+ return psp;
+}
+
+static irqreturn_t psp_irq_handler(int irq, void *data)
+{
+ struct psp_device *psp = data;
+ unsigned int status;
+
+ /* Read the interrupt status: */
+ status = ioread32(psp->io_regs + psp->vdata->intsts_reg);
+
+ /* Clear the interrupt status by writing the same value we read. */
+ iowrite32(status, psp->io_regs + psp->vdata->intsts_reg);
+
+ /* invoke subdevice interrupt handlers */
+ if (status) {
+ if (psp->sev_irq_handler)
+ psp->sev_irq_handler(irq, psp->sev_irq_data, status);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static unsigned int psp_get_capability(struct psp_device *psp)
+{
+ unsigned int val = ioread32(psp->io_regs + psp->vdata->feature_reg);
+
+ /*
+ * Check for a access to the registers. If this read returns
+ * 0xffffffff, it's likely that the system is running a broken
+ * BIOS which disallows access to the device. Stop here and
+ * fail the PSP initialization (but not the load, as the CCP
+ * could get properly initialized).
+ */
+ if (val == 0xffffffff) {
+ dev_notice(psp->dev, "psp: unable to access the device: you might be running a broken BIOS.\n");
+ return -ENODEV;
+ }
+ psp->capability.raw = val;
+
+ return 0;
+}
+
+static int psp_check_sev_support(struct psp_device *psp)
+{
+ /* Check if device supports SEV feature */
+ if (!psp->capability.sev) {
+ dev_dbg(psp->dev, "psp does not support SEV\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int psp_check_tee_support(struct psp_device *psp)
+{
+ /* Check if device supports TEE feature */
+ if (!psp->capability.tee) {
+ dev_dbg(psp->dev, "psp does not support TEE\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int psp_check_sfs_support(struct psp_device *psp)
+{
+ /* Check if device supports SFS feature */
+ if (!psp->capability.sfs) {
+ dev_dbg(psp->dev, "psp does not support SFS\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int psp_init(struct psp_device *psp)
+{
+ int ret;
+
+ if (!psp_check_sev_support(psp)) {
+ ret = sev_dev_init(psp);
+ if (ret)
+ return ret;
+ }
+
+ if (!psp_check_tee_support(psp)) {
+ ret = tee_dev_init(psp);
+ if (ret)
+ return ret;
+ }
+
+ if (!psp_check_sfs_support(psp)) {
+ ret = sfs_dev_init(psp);
+ if (ret)
+ return ret;
+ }
+
+ if (psp->vdata->platform_access) {
+ ret = platform_access_dev_init(psp);
+ if (ret)
+ return ret;
+ }
+
+ /* dbc must come after platform access as it tests the feature */
+ if (PSP_FEATURE(psp, DBC) ||
+ psp->capability.dbc_thru_ext) {
+ ret = dbc_dev_init(psp);
+ if (ret)
+ return ret;
+ }
+
+ /* HSTI uses platform access on some systems. */
+ ret = psp_init_hsti(psp);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+int psp_dev_init(struct sp_device *sp)
+{
+ struct device *dev = sp->dev;
+ struct psp_device *psp;
+ int ret;
+
+ ret = -ENOMEM;
+ psp = psp_alloc_struct(sp);
+ if (!psp)
+ goto e_err;
+
+ sp->psp_data = psp;
+
+ psp->vdata = (struct psp_vdata *)sp->dev_vdata->psp_vdata;
+ if (!psp->vdata) {
+ ret = -ENODEV;
+ dev_err(dev, "missing driver data\n");
+ goto e_err;
+ }
+
+ psp->io_regs = sp->io_map;
+ mutex_init(&psp->mailbox_mutex);
+
+ ret = psp_get_capability(psp);
+ if (ret)
+ goto e_disable;
+
+ /* Disable and clear interrupts until ready */
+ iowrite32(0, psp->io_regs + psp->vdata->inten_reg);
+ iowrite32(-1, psp->io_regs + psp->vdata->intsts_reg);
+
+ /* Request an irq */
+ ret = sp_request_psp_irq(psp->sp, psp_irq_handler, psp->name, psp);
+ if (ret) {
+ dev_err(dev, "psp: unable to allocate an IRQ\n");
+ goto e_err;
+ }
+
+ /* master device must be set for platform access */
+ if (psp->sp->set_psp_master_device)
+ psp->sp->set_psp_master_device(psp->sp);
+
+ ret = psp_init(psp);
+ if (ret)
+ goto e_irq;
+
+ /* Enable interrupt */
+ iowrite32(-1, psp->io_regs + psp->vdata->inten_reg);
+
+ dev_notice(dev, "psp enabled\n");
+
+ return 0;
+
+e_irq:
+ if (sp->clear_psp_master_device)
+ sp->clear_psp_master_device(sp);
+
+ sp_free_psp_irq(psp->sp, psp);
+e_err:
+ sp->psp_data = NULL;
+
+ dev_notice(dev, "psp initialization failed\n");
+
+ return ret;
+
+e_disable:
+ sp->psp_data = NULL;
+
+ return ret;
+}
+
+void psp_dev_destroy(struct sp_device *sp)
+{
+ struct psp_device *psp = sp->psp_data;
+
+ if (!psp)
+ return;
+
+ dbc_dev_destroy(psp);
+
+ platform_access_dev_destroy(psp);
+
+ sfs_dev_destroy(psp);
+
+ tee_dev_destroy(psp);
+
+ sev_dev_destroy(psp);
+
+ sp_free_psp_irq(sp, psp);
+
+ if (sp->clear_psp_master_device)
+ sp->clear_psp_master_device(sp);
+}
+
+void psp_set_sev_irq_handler(struct psp_device *psp, psp_irq_handler_t handler,
+ void *data)
+{
+ psp->sev_irq_data = data;
+ psp->sev_irq_handler = handler;
+}
+
+void psp_clear_sev_irq_handler(struct psp_device *psp)
+{
+ psp_set_sev_irq_handler(psp, NULL, NULL);
+}
+
+struct psp_device *psp_get_master_device(void)
+{
+ struct sp_device *sp = sp_get_psp_master_device();
+
+ return sp ? sp->psp_data : NULL;
+}
+
+int psp_restore(struct sp_device *sp)
+{
+ struct psp_device *psp = sp->psp_data;
+ int ret = 0;
+
+ if (psp->tee_data)
+ ret = tee_restore(psp);
+
+ return ret;
+}
+
+void psp_pci_init(void)
+{
+ psp_master = psp_get_master_device();
+
+ if (!psp_master)
+ return;
+
+ sev_pci_init();
+}
+
+void psp_pci_exit(void)
+{
+ if (!psp_master)
+ return;
+
+ sev_pci_exit();
+}