[PATCH 2/2] habv4: use hab rom implementation of report_event

[Stefan Kerkmann]

The existing habv4 rom vector table had some mismatches in the API of
the function pointers which broke calling into the HAB rom - mainly
observed with the `report_event` function. The suspected culprit here is
the `bytes` pointer which was `uint32_t*` vs. the documented `size_t*`.

When compiled using the ILP32 data model e.g. for 32-Bit systems both
referrenced values have the same width, but once compiled for (I)LP64
they differ as `size_t` is 64-Bit wide there. This seems to trigger a
memory corruption once that pointer is passed to the HAB boot rom code
and dereferenced there, the root cause wasn't investigated further
though.

As this implementation has only been tested on an imx8mm and imx8nm board
I'm beeing defensive and only enable it for these targets. Once all
SOCs of the family have been verified to work correctly the OCRAM
readout workaround can be removed.

Signed-off-by: Stefan Kerkmann <s.kerkmann at pengutronix.de>
---
 drivers/hab/habv4.c | 43 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 38 insertions(+), 5 deletions(-)

diff --git a/drivers/hab/habv4.c b/drivers/hab/habv4.c
index dfa0207435..db5862a92a 100644
--- a/drivers/hab/habv4.c
+++ b/drivers/hab/habv4.c
@@ -180,6 +180,33 @@ enum hab_sip_cmd {
 	FSL_SIP_HAB_GET_VERSION = 0x07,
 };
 
+static enum hab_status hab_sip_report_event(enum hab_status status,
+					    uint32_t index, uint8_t *event,
+					    size_t *bytes)
+{
+	struct arm_smccc_res res;
+
+	v8_flush_dcache_range((unsigned long)bytes,
+			      (unsigned long)bytes + sizeof(*bytes));
+
+	if (event)
+		v8_flush_dcache_range((unsigned long)event,
+				      (unsigned long)event + *bytes);
+
+	arm_smccc_smc(FSL_SIP_HAB, FSL_SIP_HAB_REPORT_EVENT,
+		      (unsigned long)index, (unsigned long)event,
+		      (unsigned long)bytes, 0, 0, 0, &res);
+
+	v8_inv_dcache_range((unsigned long)bytes,
+			    (unsigned long)bytes + sizeof(*bytes));
+
+	if (event)
+		v8_inv_dcache_range((unsigned long)event,
+				    (unsigned long)event + *bytes);
+
+	return (enum hab_status)res.a0;
+}
+
 static enum hab_status hab_sip_report_status(enum hab_config *config,
 					     enum habv4_state *state)
 {
@@ -235,10 +262,6 @@ static enum hab_status imx8m_read_sram_events(enum hab_status status,
 
 	if (cpu_is_mx8mq())
 		sram = (char *)IMX8MQ_ROM_OCRAM_ADDRESS;
-	else if (cpu_is_mx8mm())
-		sram = (char *)IMX8MM_ROM_OCRAM_ADDRESS;
-	else if (cpu_is_mx8mn())
-		sram = (char *)IMX8MN_ROM_OCRAM_ADDRESS;
 	else if (cpu_is_mx8mp())
 		sram = (char *)IMX8MP_ROM_OCRAM_ADDRESS;
 	else
@@ -292,9 +315,19 @@ static enum hab_status imx8m_read_sram_events(enum hab_status status,
 	return HAB_STATUS_FAILURE;
 }
 
+static enum hab_status imx8m_report_event(enum hab_status status,
+					  uint32_t index, uint8_t *event,
+					  size_t *bytes)
+{
+	if (cpu_is_mx8mm() || cpu_is_mx8mn())
+		return hab_sip_report_event(status, index, event, bytes);
+	else
+		return imx8m_read_sram_events(status, index, event, bytes);
+}
+
 struct habv4_rvt hab_smc_ops = {
 	.header = { .tag = 0xdd },
-	.report_event = imx8m_read_sram_events,
+	.report_event = imx8m_report_event,
 	.report_status = hab_sip_report_status,
 };
 

-- 
2.39.2