[Qemu-arm] [PATCH v2 5/5] arm: highbank: Implement PSCI and dummy monitor

[Peter Crosthwaite]

Firstly, enable monitor mode and PSCI, both are which are features of
this board.

In addition to PSCI, this board also uses SMC for cache maintainence
ops. This means we need a secure monitor to catch these and nop them.
Use the ARM boot board-setup feature to implement this. All traps to
monitor mode implement the nop.

Signed-off-by: Peter Crosthwaite <address@hidden>
---
Changed since v1:
fallthrough all of trap table to nop implementation
use movw for table address
leave loader at 0
Move MVBAR (and blob to non-zero)
Split nop implementation from MVBAR setup
set secure boot for board
implement NS switch in blob
Changed since RFC:
Use bootloader callback to load blob.
Change "firmware" to "board-setup" for consistency.
Tweak commit message.

 hw/arm/highbank.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 56 insertions(+), 10 deletions(-)

diff --git a/hw/arm/highbank.c b/hw/arm/highbank.c
index be04b27..f3578a3 100644
--- a/hw/arm/highbank.c
+++ b/hw/arm/highbank.c
@@ -32,10 +32,55 @@
 #define SMP_BOOT_REG            0x40
 #define MPCORE_PERIPHBASE       0xfff10000
 
+#define MVBAR_ADDR              0x200
+
 #define NIRQ_GIC                160
 
 /* Board init.  */
 
+/* MVBAR_ADDR is limited by precision of movw */
+
+QEMU_BUILD_BUG_ON(MVBAR_ADDR >= (1 << 16));
+
+#define ARMV7_IMM16(x) (extract32((x),  0, 12) | \
+                        extract32((x), 12,  4) << 16)
+
+static void hb_write_board_setup(ARMCPU *cpu,
+                                 const struct arm_boot_info *info)
+{
+    int n;
+    uint32_t board_setup_blob[] = {
+        /* MVBAR_ADDR */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+        0xe320f000, /* nop */
+#define ERET_ADDR (MVBAR_ADDR + 8 * sizeof(uint32_t))
+        0xe58fe008, /* save lr */
+        0xe8dfc000, /* exception return */
+        0,
+        0,
+        0, /* exception return link will end up here */
+#define BOARD_SETUP_ADDR (ERET_ADDR + 5 * sizeof(uint32_t))
+        0xe3000000 + ARMV7_IMM16(MVBAR_ADDR), /* movw r0, MVBAR_ADDR */
+        0xee0c0f30, /* mcr p15, 0, r0, c12, c0, 1 - set mvbar */
+        0xee110f11, /* mrc p15, 0, r0, c1 , c1, 0 - get scr */
+        0xe3810001, /* orr r0, #1 - set NS */
+        0xee010f11, /* mcr p15, 0, r0, c1 , c1, 0 - set scr */
+        0xe1600070, /* smc - go to monitor mode to flush NS change */
+        0xe12fff1e, /* bx lr - return to caller */
+    };
+    for (n = 0; n < ARRAY_SIZE(board_setup_blob); n++) {
+        board_setup_blob[n] = tswap32(board_setup_blob[n]);
+    }
+    rom_add_blob_fixed("board-setup", board_setup_blob,
+                       sizeof(board_setup_blob), MVBAR_ADDR);
+}
+
 static void hb_write_secondary(ARMCPU *cpu, const struct arm_boot_info *info)
 {
     int n;
@@ -248,16 +293,13 @@ static void calxeda_init(MachineState *machine, enum 
cxmachines machine_id)
         cpuobj = object_new(object_class_get_name(oc));
         cpu = ARM_CPU(cpuobj);
 
-        /* By default A9 and A15 CPUs have EL3 enabled.  This board does not
-         * currently support EL3 so the CPU EL3 property is disabled before
-         * realization.
-         */
-        if (object_property_find(cpuobj, "has_el3", NULL)) {
-            object_property_set_bool(cpuobj, false, "has_el3", &err);
-            if (err) {
-                error_report_err(err);
-                exit(1);
-            }
+        object_property_set_int(cpuobj, QEMU_PSCI_CONDUIT_SMC,
+                                "psci-conduit", &error_abort);
+
+        if (n) {
+            /* Secondary CPUs start in PSCI powered-down state */
+            object_property_set_bool(cpuobj, true,
+                                     "start-powered-off", &error_abort);
         }
 
         if (object_property_find(cpuobj, "reset-cbar", NULL)) {
@@ -378,6 +420,10 @@ static void calxeda_init(MachineState *machine, enum 
cxmachines machine_id)
     highbank_binfo.loader_start = 0;
     highbank_binfo.write_secondary_boot = hb_write_secondary;
     highbank_binfo.secondary_cpu_reset_hook = hb_reset_secondary;
+    highbank_binfo.board_setup_addr = BOARD_SETUP_ADDR;
+    highbank_binfo.write_board_setup = hb_write_board_setup;
+    highbank_binfo.secure_board_setup = true;
+
     arm_load_kernel(ARM_CPU(first_cpu), &highbank_binfo);
 }
 
-- 
1.9.1