hw/arm: Correctly disable FPU/DSP for some ARMSSE-based boards

The SSE-200 hardware has configurable integration settings which
determine whether its two CPUs have the FPU and DSP:
 * CPU0_FPU (default 0)
 * CPU0_DSP (default 0)
 * CPU1_FPU (default 1)
 * CPU1_DSP (default 1)

Similarly, the IoTKit has settings for its single CPU:
 * CPU0_FPU (default 1)
 * CPU0_DSP (default 1)

Of our four boards that use either the IoTKit or the SSE-200:
 * mps2-an505, mps2-an521 and musca-a use the default settings
 * musca-b1 enables FPU and DSP on both CPUs

Currently QEMU models all these boards using CPUs with
both FPU and DSP enabled. This means that we are incorrect
for mps2-an521 and musca-a, which should not have FPU or DSP
on CPU0.

Create QOM properties on the ARMSSE devices corresponding to the
default h/w integration settings, and make the Musca-B1 board
enable FPU and DSP on both CPUs. This fixes the mps2-an521
and musca-a behaviour, and leaves the musca-b1 and mps2-an505
behaviour unchanged.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20190517174046.11146-5-peter.maydell@linaro.org

1 files changed, 8 insertions, 0 deletions

diff --git a/hw/arm/musca.c b/hw/arm/musca.c
index 825d80e..ddd8842 100644
--- a/hw/arm/musca.c
+++ b/hw/arm/musca.c
@@ -385,6 +385,14 @@ static void musca_init(MachineState *machine)
     qdev_prop_set_uint32(ssedev, "init-svtor", mmc->init_svtor);
     qdev_prop_set_uint32(ssedev, "SRAM_ADDR_WIDTH", mmc->sram_addr_width);
     qdev_prop_set_uint32(ssedev, "MAINCLK", SYSCLK_FRQ);
+    /*
+     * Musca-A takes the default SSE-200 FPU/DSP settings (ie no for
+     * CPU0 and yes for CPU1); Musca-B1 explicitly enables them for CPU0.
+     */
+    if (mmc->type == MUSCA_B1) {
+        qdev_prop_set_bit(ssedev, "CPU0_FPU", true);
+        qdev_prop_set_bit(ssedev, "CPU0_DSP", true);
+    }
     object_property_set_bool(OBJECT(&mms->sse), true, "realized",
                              &error_fatal);