crypto: ccree - check that cryptocell reset completed

In case of driver probe and pm resume we need to check that the cryptocell
hardware reset cycle is completed. during the reset cycle that Cryptocell
provide read only access to the APB interface which allows to verify
through the CC registers that the reset is completed. Until reset
completion we assume that any write/crypto operation is blocked.

Signed-off-by: Ofir Drang <ofir.drang@arm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/ccree/cc_driver.c b/drivers/crypto/ccree/cc_driver.c
index 0f80cb4f79fb14ba679ae58689777508f423b3fd..1e73d32148ddd6d7b201e7b9c27cbbe736dad307 100644 (file)
--- a/drivers/crypto/ccree/cc_driver.c
+++ b/drivers/crypto/ccree/cc_driver.c
@@ -48,6 +48,7 @@ struct cc_hw_data {
 };
 
 #define CC_NUM_IDRS 4
+#define CC_HW_RESET_LOOP_COUNT 10
 
 /* Note: PIDR3 holds CMOD/Rev so ignored for HW identification purposes */
 static const u32 pidr_0124_offsets[CC_NUM_IDRS] = {
@@ -188,6 +189,31 @@ static irqreturn_t cc_isr(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
+bool cc_wait_for_reset_completion(struct cc_drvdata *drvdata)
+{
+       unsigned int val;
+       unsigned int i;
+
+       /* 712/710/63 has no reset completion indication, always return true */
+       if (drvdata->hw_rev <= CC_HW_REV_712)
+               return true;
+
+       for (i = 0; i < CC_HW_RESET_LOOP_COUNT; i++) {
+               /* in cc7x3 NVM_IS_IDLE indicates that CC reset is
+                *  completed and device is fully functional
+                */
+               val = cc_ioread(drvdata, CC_REG(NVM_IS_IDLE));
+               if (val & CC_NVM_IS_IDLE_MASK) {
+                       /* hw indicate reset completed */
+                       return true;
+               }
+               /* allow scheduling other process on the processor */
+               schedule();
+       }
+       /* reset not completed */
+       return false;
+}
+
 int init_cc_regs(struct cc_drvdata *drvdata, bool is_probe)
 {
        unsigned int val, cache_params;
@@ -343,6 +369,11 @@ static int init_cc_resources(struct platform_device *plat_dev)
 
        new_drvdata->sec_disabled = cc_sec_disable;
 
+       /* wait for Crytpcell reset completion */
+       if (!cc_wait_for_reset_completion(new_drvdata)) {
+               dev_err(dev, "Cryptocell reset not completed");
+       }
+
        if (hw_rev->rev <= CC_HW_REV_712) {
                /* Verify correct mapping */
                val = cc_ioread(new_drvdata, new_drvdata->sig_offset);
@@ -398,7 +429,7 @@ static int init_cc_resources(struct platform_device *plat_dev)
        if (rc) {
                dev_err(dev, "Could not register to interrupt %d\n",
                        new_drvdata->irq);
-               return rc;
+               goto post_clk_err;
        }
        dev_dbg(dev, "Registered to IRQ: %d\n", new_drvdata->irq);
 

diff --git a/drivers/crypto/ccree/cc_driver.h b/drivers/crypto/ccree/cc_driver.h
index b76181335c08afa01ba4b15ba00eb17421eb771b..579eecae4825a7fcb47f5bfbd835272777b1143f 100644 (file)
--- a/drivers/crypto/ccree/cc_driver.h
+++ b/drivers/crypto/ccree/cc_driver.h
@@ -67,6 +67,8 @@ enum cc_std_body {
 
 #define CC_SECURITY_DISABLED_MASK BIT(CC_SECURITY_DISABLED_VALUE_BIT_SHIFT)
 
+#define CC_NVM_IS_IDLE_MASK BIT(CC_NVM_IS_IDLE_VALUE_BIT_SHIFT)
+
 #define AXIM_MON_COMP_VALUE GENMASK(CC_AXIM_MON_COMP_VALUE_BIT_SIZE + \
                                    CC_AXIM_MON_COMP_VALUE_BIT_SHIFT, \
                                    CC_AXIM_MON_COMP_VALUE_BIT_SHIFT)
@@ -216,6 +218,7 @@ static inline void dump_byte_array(const char *name, const u8 *the_array,
                __dump_byte_array(name, the_array, size);
 }
 
+bool cc_wait_for_reset_completion(struct cc_drvdata *drvdata);
 int init_cc_regs(struct cc_drvdata *drvdata, bool is_probe);
 void fini_cc_regs(struct cc_drvdata *drvdata);
 int cc_clk_on(struct cc_drvdata *drvdata);

diff --git a/drivers/crypto/ccree/cc_host_regs.h b/drivers/crypto/ccree/cc_host_regs.h
index d0764147573fc26660b5a1176004f7da8cff3ea3..ad1acb105f2d1c551b8eca81a23c9a3ea841c6d8 100644 (file)
--- a/drivers/crypto/ccree/cc_host_regs.h
+++ b/drivers/crypto/ccree/cc_host_regs.h
@@ -114,6 +114,9 @@
 #define CC_HOST_ICR_DSCRPTR_WATERMARK_QUEUE0_CLEAR_BIT_SIZE    0x1UL
 #define CC_HOST_ICR_AXIM_COMP_INT_CLEAR_BIT_SHIFT      0x17UL
 #define CC_HOST_ICR_AXIM_COMP_INT_CLEAR_BIT_SIZE       0x1UL
+#define CC_NVM_IS_IDLE_REG_OFFSET       0x0A10UL
+#define CC_NVM_IS_IDLE_VALUE_BIT_SHIFT  0x0UL
+#define CC_NVM_IS_IDLE_VALUE_BIT_SIZE   0x1UL
 #define CC_SECURITY_DISABLED_REG_OFFSET                0x0A1CUL
 #define CC_SECURITY_DISABLED_VALUE_BIT_SHIFT   0x0UL
 #define CC_SECURITY_DISABLED_VALUE_BIT_SIZE    0x1UL

diff --git a/drivers/crypto/ccree/cc_pm.c b/drivers/crypto/ccree/cc_pm.c
index 2dad9c9543c6990236ae3816d6aaf27c0635c361..20f7f3d34e27afdc23b321be6355b598c269df00 100644 (file)
--- a/drivers/crypto/ccree/cc_pm.c
+++ b/drivers/crypto/ccree/cc_pm.c
@@ -49,6 +49,11 @@ int cc_pm_resume(struct device *dev)
                dev_err(dev, "failed getting clock back on. We're toast.\n");
                return rc;
        }
+       /* wait for Crytpcell reset completion */
+       if (!cc_wait_for_reset_completion(drvdata)) {
+               dev_err(dev, "Cryptocell reset not completed");
+               return -EBUSY;
+       }
 
        cc_iowrite(drvdata, CC_REG(HOST_POWER_DOWN_EN), POWER_DOWN_DISABLE);
        rc = init_cc_regs(drvdata, false);