Fix TZC-400 peripheral detection
The TZC-400 driver implementation incorrectly uses the component
ID registers to detect the TZC-400 peripheral. As all ARM
peripherals share the same component ID, it doesn't allow to
uniquely identify the TZC-400 peripheral. This patch fixes the
TZC-400 driver by relying on the `part_number_0` and
`part_number_1` fields in the `PID` registers instead.
The `tzc_read_component_id` function has been replaced by
`tzc_read_peripheral_id`, which reads the 'part_number' values
and compares them with the TZC-400 peripheral ID.
Also, it adds a debug assertion to detect when the TZC driver
initialisation function is called multiple times.
Change-Id: I35949f6501a51c0a794144cd1c3a6db62440dce6
diff --git a/drivers/arm/tzc400/tzc400.c b/drivers/arm/tzc400/tzc400.c
index 4b72a2b..940e00e 100644
--- a/drivers/arm/tzc400/tzc400.c
+++ b/drivers/arm/tzc400/tzc400.c
@@ -118,14 +118,13 @@
REGION_NUM_OFF(region), val);
}
-static uint32_t tzc_read_component_id(uintptr_t base)
+static unsigned int tzc_read_peripheral_id(uintptr_t base)
{
- uint32_t id;
+ unsigned int id;
- id = mmio_read_8(base + CID0_OFF);
- id |= (mmio_read_8(base + CID1_OFF) << 8);
- id |= (mmio_read_8(base + CID2_OFF) << 16);
- id |= (mmio_read_8(base + CID3_OFF) << 24);
+ id = mmio_read_8(base + PID0_OFF);
+ /* Masks jep106_id_3_0 part in PID1 */
+ id |= ((mmio_read_8(base + PID1_OFF) & 0xF) << 8);
return id;
}
@@ -166,17 +165,21 @@
void tzc_init(uintptr_t base)
{
- uint32_t tzc_id, tzc_build;
+ unsigned int tzc_id;
+ unsigned int tzc_build;
assert(base);
+
+ /* Assert if already initialised */
+ assert(!tzc.base);
+
tzc.base = base;
/*
- * We expect to see a tzc400. Check component ID. The TZC-400 TRM shows
- * component ID is expected to be "0xB105F00D".
+ * We expect to see a tzc400. Check peripheral ID.
*/
- tzc_id = tzc_read_component_id(tzc.base);
- if (tzc_id != TZC400_COMPONENT_ID) {
+ tzc_id = tzc_read_peripheral_id(tzc.base);
+ if (tzc_id != TZC400_PERIPHERAL_ID) {
ERROR("TZC : Wrong device ID (0x%x).\n", tzc_id);
panic();
}