[RFC PATCH v2 20/32] crypto: ccp: Add Platform Security Processor (PSP) interface support

From: Brijesh Singh
Date: Thu Mar 02 2017 - 10:37:28 EST


AMD Platform Security Processor (PSP) is a dedicated processor that
provides the support for encrypting the guest memory in a Secure Encrypted
Virtualiztion (SEV) mode, along with software-based Tursted Executation
Environment (TEE) to enable the third-party tursted applications.

Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
drivers/crypto/ccp/Kconfig | 7 +
drivers/crypto/ccp/Makefile | 1
drivers/crypto/ccp/psp-dev.c | 211 ++++++++++++++++++++++++++++++++++++++++++
drivers/crypto/ccp/psp-dev.h | 102 ++++++++++++++++++++
drivers/crypto/ccp/sp-dev.c | 16 +++
drivers/crypto/ccp/sp-dev.h | 34 +++++++
drivers/crypto/ccp/sp-pci.c | 4 +
7 files changed, 374 insertions(+), 1 deletion(-)
create mode 100644 drivers/crypto/ccp/psp-dev.c
create mode 100644 drivers/crypto/ccp/psp-dev.h

diff --git a/drivers/crypto/ccp/Kconfig b/drivers/crypto/ccp/Kconfig
index bc08f03..59c207e 100644
--- a/drivers/crypto/ccp/Kconfig
+++ b/drivers/crypto/ccp/Kconfig
@@ -34,4 +34,11 @@ config CRYPTO_DEV_CCP
Provides the interface to use the AMD Cryptographic Coprocessor
which can be used to offload encryption operations such as SHA,
AES and more.
+
+config CRYPTO_DEV_PSP
+ bool "Platform Security Processor interface"
+ default y
+ help
+ Provide the interface for AMD Platform Security Processor (PSP) device.
+
endif
diff --git a/drivers/crypto/ccp/Makefile b/drivers/crypto/ccp/Makefile
index 8127e18..12e569d 100644
--- a/drivers/crypto/ccp/Makefile
+++ b/drivers/crypto/ccp/Makefile
@@ -6,6 +6,7 @@ ccp-$(CONFIG_CRYPTO_DEV_CCP) += ccp-dev.o \
ccp-dev-v3.o \
ccp-dev-v5.o \
ccp-dmaengine.o
+ccp-$(CONFIG_CRYPTO_DEV_PSP) += psp-dev.o

obj-$(CONFIG_CRYPTO_DEV_CCP_CRYPTO) += ccp-crypto.o
ccp-crypto-objs := ccp-crypto-main.o \
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
new file mode 100644
index 0000000..6f64aa7
--- /dev/null
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -0,0 +1,211 @@
+/*
+ * AMD Platform Security Processor (PSP) interface
+ *
+ * Copyright (C) 2016 Advanced Micro Devices, Inc.
+ *
+ * Author: Brijesh Singh <brijesh.singh@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/spinlock_types.h>
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/hw_random.h>
+#include <linux/ccp.h>
+
+#include "sp-dev.h"
+#include "psp-dev.h"
+
+static LIST_HEAD(psp_devs);
+static DEFINE_SPINLOCK(psp_devs_lock);
+
+const struct psp_vdata psp_entry = {
+ .offset = 0x10500,
+};
+
+void psp_add_device(struct psp_device *psp)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&psp_devs_lock, flags);
+
+ list_add_tail(&psp->entry, &psp_devs);
+
+ spin_unlock_irqrestore(&psp_devs_lock, flags);
+}
+
+void psp_del_device(struct psp_device *psp)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&psp_devs_lock, flags);
+
+ list_del(&psp->entry);
+ spin_unlock_irqrestore(&psp_devs_lock, flags);
+}
+
+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;
+}
+
+irqreturn_t psp_irq_handler(int irq, void *data)
+{
+ unsigned int status;
+ irqreturn_t ret = IRQ_HANDLED;
+ struct psp_device *psp = data;
+
+ /* read the interrupt status */
+ status = ioread32(psp->io_regs + PSP_P2CMSG_INTSTS);
+
+ /* invoke subdevice interrupt handlers */
+ if (status) {
+ if (psp->sev_irq_handler)
+ ret = psp->sev_irq_handler(irq, psp->sev_irq_data);
+ }
+
+ /* clear the interrupt status */
+ iowrite32(status, psp->io_regs + PSP_P2CMSG_INTSTS);
+
+ return ret;
+}
+
+static int psp_init(struct psp_device *psp)
+{
+ psp_add_device(psp);
+
+ sev_dev_init(psp);
+
+ 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_data->psp_vdata;
+ if (!psp->vdata) {
+ ret = -ENODEV;
+ dev_err(dev, "missing driver data\n");
+ goto e_err;
+ }
+
+ psp->io_regs = sp->io_map + psp->vdata->offset;
+
+ /* Disable and clear interrupts until ready */
+ iowrite32(0, psp->io_regs + PSP_P2CMSG_INTEN);
+ iowrite32(0xffffffff, psp->io_regs + PSP_P2CMSG_INTSTS);
+
+ dev_dbg(dev, "requesting an IRQ ...\n");
+ /* 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;
+ }
+
+ sp_set_psp_master(sp);
+
+ dev_dbg(dev, "initializing psp\n");
+ ret = psp_init(psp);
+ if (ret) {
+ dev_err(dev, "failed to init psp\n");
+ goto e_irq;
+ }
+
+ /* Enable interrupt */
+ dev_dbg(dev, "Enabling interrupts ...\n");
+ iowrite32(7, psp->io_regs + PSP_P2CMSG_INTEN);
+
+ dev_notice(dev, "psp enabled\n");
+
+ return 0;
+
+e_irq:
+ sp_free_psp_irq(psp->sp, psp);
+e_err:
+ sp->psp_data = NULL;
+
+ dev_notice(dev, "psp initialization failed\n");
+
+ return ret;
+}
+
+void psp_dev_destroy(struct sp_device *sp)
+{
+ struct psp_device *psp = sp->psp_data;
+
+ sev_dev_destroy(psp);
+
+ sp_free_psp_irq(sp, psp);
+
+ psp_del_device(psp);
+}
+
+int psp_dev_resume(struct sp_device *sp)
+{
+ sev_dev_resume(sp->psp_data);
+ return 0;
+}
+
+int psp_dev_suspend(struct sp_device *sp, pm_message_t state)
+{
+ sev_dev_suspend(sp->psp_data, state);
+ return 0;
+}
+
+int psp_request_sev_irq(struct psp_device *psp, irq_handler_t handler,
+ void *data)
+{
+ psp->sev_irq_data = data;
+ psp->sev_irq_handler = handler;
+
+ return 0;
+}
+
+int psp_free_sev_irq(struct psp_device *psp, void *data)
+{
+ if (psp->sev_irq_handler) {
+ psp->sev_irq_data = NULL;
+ psp->sev_irq_handler = NULL;
+ }
+
+ return 0;
+}
+
+struct psp_device *psp_get_master_device(void)
+{
+ struct sp_device *sp = sp_get_psp_master_device();
+
+ return sp ? sp->psp_data : NULL;
+}
diff --git a/drivers/crypto/ccp/psp-dev.h b/drivers/crypto/ccp/psp-dev.h
new file mode 100644
index 0000000..bbd3d96
--- /dev/null
+++ b/drivers/crypto/ccp/psp-dev.h
@@ -0,0 +1,102 @@
+/*
+ * AMD Platform Security Processor (PSP) interface driver
+ *
+ * Copyright (C) 2016 Advanced Micro Devices, Inc.
+ *
+ * Author: Brijesh Singh <brijesh.singh@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __PSP_DEV_H__
+#define __PSP_DEV_H__
+
+#include <linux/device.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/dmapool.h>
+#include <linux/hw_random.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/dmaengine.h>
+
+#include "sp-dev.h"
+
+#define PSP_P2CMSG_INTEN 0x0110
+#define PSP_P2CMSG_INTSTS 0x0114
+
+#define PSP_C2PMSG_ATTR_0 0x0118
+#define PSP_C2PMSG_ATTR_1 0x011c
+#define PSP_C2PMSG_ATTR_2 0x0120
+#define PSP_C2PMSG_ATTR_3 0x0124
+#define PSP_P2CMSG_ATTR_0 0x0128
+
+#define PSP_CMDRESP_CMD_SHIFT 16
+#define PSP_CMDRESP_IOC BIT(0)
+#define PSP_CMDRESP_RESP BIT(31)
+#define PSP_CMDRESP_ERR_MASK 0xffff
+
+#define MAX_PSP_NAME_LEN 16
+
+struct psp_device {
+ struct list_head entry;
+
+ struct psp_vdata *vdata;
+ char name[MAX_PSP_NAME_LEN];
+
+ struct device *dev;
+ struct sp_device *sp;
+
+ void __iomem *io_regs;
+
+ irq_handler_t sev_irq_handler;
+ void *sev_irq_data;
+
+ void *sev_data;
+};
+
+void psp_add_device(struct psp_device *psp);
+void psp_del_device(struct psp_device *psp);
+
+int psp_request_sev_irq(struct psp_device *psp, irq_handler_t handler,
+ void *data);
+int psp_free_sev_irq(struct psp_device *psp, void *data);
+
+struct psp_device *psp_get_master_device(void);
+
+#ifdef CONFIG_AMD_SEV
+
+int sev_dev_init(struct psp_device *psp);
+void sev_dev_destroy(struct psp_device *psp);
+int sev_dev_resume(struct psp_device *psp);
+int sev_dev_suspend(struct psp_device *psp, pm_message_t state);
+
+#else
+
+static inline int sev_dev_init(struct psp_device *psp)
+{
+ return -ENODEV;
+}
+
+static inline void sev_dev_destroy(struct psp_device *psp) { }
+
+static inline int sev_dev_resume(struct psp_device *psp)
+{
+ return -ENODEV;
+}
+
+static inline int sev_dev_suspend(struct psp_device *psp, pm_message_t state)
+{
+ return -ENODEV;
+}
+
+#endif /* __AMD_SEV_H */
+
+#endif /* __PSP_DEV_H */
+
diff --git a/drivers/crypto/ccp/sp-dev.c b/drivers/crypto/ccp/sp-dev.c
index e47fb8e..975a435 100644
--- a/drivers/crypto/ccp/sp-dev.c
+++ b/drivers/crypto/ccp/sp-dev.c
@@ -212,6 +212,8 @@ int sp_init(struct sp_device *sp)
if (sp->dev_data->ccp_vdata)
ccp_dev_init(sp);

+ if (sp->dev_data->psp_vdata)
+ psp_dev_init(sp);
return 0;
}

@@ -220,6 +222,9 @@ void sp_destroy(struct sp_device *sp)
if (sp->dev_data->ccp_vdata)
ccp_dev_destroy(sp);

+ if (sp->dev_data->psp_vdata)
+ psp_dev_destroy(sp);
+
sp_del_device(sp);
}

@@ -233,6 +238,12 @@ int sp_suspend(struct sp_device *sp, pm_message_t state)
return ret;
}

+ if (sp->dev_data->psp_vdata) {
+ ret = psp_dev_suspend(sp, state);
+ if (ret)
+ return ret;
+ }
+
return 0;
}

@@ -246,6 +257,11 @@ int sp_resume(struct sp_device *sp)
return ret;
}

+ if (sp->dev_data->psp_vdata) {
+ ret = psp_dev_resume(sp);
+ if (ret)
+ return ret;
+ }
return 0;
}

diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h
index 9a8a8f8..aeff7a0 100644
--- a/drivers/crypto/ccp/sp-dev.h
+++ b/drivers/crypto/ccp/sp-dev.h
@@ -40,12 +40,18 @@ struct ccp_vdata {
const unsigned int offset;
};

+struct psp_vdata {
+ const unsigned int version;
+ const struct psp_actions *perform;
+ const unsigned int offset;
+};
+
/* Structure to hold SP device data */
struct sp_dev_data {
const unsigned int bar;

const struct ccp_vdata *ccp_vdata;
- const void *psp_vdata;
+ const struct psp_vdata *psp_vdata;
};

struct sp_device {
@@ -137,4 +143,30 @@ static inline int ccp_dev_resume(struct sp_device *sp)

#endif /* CONFIG_CRYPTO_DEV_CCP */

+#ifdef CONFIG_CRYPTO_DEV_PSP
+
+int psp_dev_init(struct sp_device *sp);
+void psp_dev_destroy(struct sp_device *sp);
+
+int psp_dev_suspend(struct sp_device *sp, pm_message_t state);
+int psp_dev_resume(struct sp_device *sp);
+#else /* !CONFIG_CRYPTO_DEV_CCP */
+
+static inline int psp_dev_init(struct sp_device *sp)
+{
+ return 0;
+}
+static inline void psp_dev_destroy(struct sp_device *sp) { }
+
+static inline int psp_dev_suspend(struct sp_device *sp, pm_message_t state)
+{
+ return 0;
+}
+static inline int psp_dev_resume(struct sp_device *sp)
+{
+ return 0;
+}
+
+#endif /* CONFIG_CRYPTO_DEV_CCP */
+
#endif
diff --git a/drivers/crypto/ccp/sp-pci.c b/drivers/crypto/ccp/sp-pci.c
index 0960e2d..4999662 100644
--- a/drivers/crypto/ccp/sp-pci.c
+++ b/drivers/crypto/ccp/sp-pci.c
@@ -271,6 +271,7 @@ static int sp_pci_resume(struct pci_dev *pdev)
extern struct ccp_vdata ccpv3_pci;
extern struct ccp_vdata ccpv5a;
extern struct ccp_vdata ccpv5b;
+extern struct psp_vdata psp_entry;

static const struct sp_dev_data dev_data[] = {
{
@@ -284,6 +285,9 @@ static const struct sp_dev_data dev_data[] = {
#ifdef CONFIG_CRYPTO_DEV_CCP
.ccp_vdata = &ccpv5a,
#endif
+#ifdef CONFIG_CRYPTO_DEV_PSP
+ .psp_vdata = &psp_entry
+#endif
},
{
.bar = 2,