linux/drivers/crypto/ccree/cc_fips.c

121 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2012-2018 ARM Limited or its affiliates. */
#include <linux/kernel.h>
#include <linux/fips.h>
#include "cc_driver.h"
#include "cc_fips.h"
static void fips_dsr(unsigned long devarg);
struct cc_fips_handle {
struct tasklet_struct tasklet;
};
/* The function called once at driver entry point to check
* whether TEE FIPS error occurred.
*/
static bool cc_get_tee_fips_status(struct cc_drvdata *drvdata)
{
u32 reg;
reg = cc_ioread(drvdata, CC_REG(GPR_HOST));
return (reg == (CC_FIPS_SYNC_TEE_STATUS | CC_FIPS_SYNC_MODULE_OK));
}
/*
* This function should push the FIPS REE library status towards the TEE library
* by writing the error state to HOST_GPR0 register.
*/
void cc_set_ree_fips_status(struct cc_drvdata *drvdata, bool status)
{
int val = CC_FIPS_SYNC_REE_STATUS;
if (drvdata->hw_rev < CC_HW_REV_712)
return;
val |= (status ? CC_FIPS_SYNC_MODULE_OK : CC_FIPS_SYNC_MODULE_ERROR);
cc_iowrite(drvdata, CC_REG(HOST_GPR0), val);
}
void cc_fips_fini(struct cc_drvdata *drvdata)
{
struct cc_fips_handle *fips_h = drvdata->fips_handle;
if (drvdata->hw_rev < CC_HW_REV_712 || !fips_h)
return;
/* Kill tasklet */
tasklet_kill(&fips_h->tasklet);
kfree(fips_h);
drvdata->fips_handle = NULL;
}
void fips_handler(struct cc_drvdata *drvdata)
{
struct cc_fips_handle *fips_handle_ptr = drvdata->fips_handle;
if (drvdata->hw_rev < CC_HW_REV_712)
return;
tasklet_schedule(&fips_handle_ptr->tasklet);
}
static inline void tee_fips_error(struct device *dev)
{
if (fips_enabled)
panic("ccree: TEE reported cryptographic error in fips mode!\n");
else
dev_err(dev, "TEE reported error!\n");
}
/* Deferred service handler, run as interrupt-fired tasklet */
static void fips_dsr(unsigned long devarg)
{
struct cc_drvdata *drvdata = (struct cc_drvdata *)devarg;
struct device *dev = drvdata_to_dev(drvdata);
u32 irq, state, val;
irq = (drvdata->irq & (CC_GPR0_IRQ_MASK));
if (irq) {
state = cc_ioread(drvdata, CC_REG(GPR_HOST));
if (state != (CC_FIPS_SYNC_TEE_STATUS | CC_FIPS_SYNC_MODULE_OK))
tee_fips_error(dev);
}
/* after verifing that there is nothing to do,
* unmask AXI completion interrupt.
*/
val = (CC_REG(HOST_IMR) & ~irq);
cc_iowrite(drvdata, CC_REG(HOST_IMR), val);
}
/* The function called once at driver entry point .*/
int cc_fips_init(struct cc_drvdata *p_drvdata)
{
struct cc_fips_handle *fips_h;
struct device *dev = drvdata_to_dev(p_drvdata);
if (p_drvdata->hw_rev < CC_HW_REV_712)
return 0;
fips_h = kzalloc(sizeof(*fips_h), GFP_KERNEL);
if (!fips_h)
return -ENOMEM;
p_drvdata->fips_handle = fips_h;
dev_dbg(dev, "Initializing fips tasklet\n");
tasklet_init(&fips_h->tasklet, fips_dsr, (unsigned long)p_drvdata);
if (!cc_get_tee_fips_status(p_drvdata))
tee_fips_error(dev);
return 0;
}