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, 7 insertions, 0 deletions

diff --git a/include/hw/arm/armsse.h b/include/hw/arm/armsse.h
index 81e082cccf..84080c2299 100644
--- a/include/hw/arm/armsse.h
+++ b/include/hw/arm/armsse.h
@@ -50,6 +50,11 @@
  *    address of each SRAM bank (and thus the total amount of internal SRAM)
  *  + QOM property "init-svtor" sets the initial value of the CPU SVTOR register
  *    (where it expects to load the PC and SP from the vector table on reset)
+ *  + QOM properties "CPU0_FPU", "CPU0_DSP", "CPU1_FPU" and "CPU1_DSP" which
+ *    set whether the CPUs have the FPU and DSP features present. The default
+ *    (matching the hardware) is that for CPU0 in an IoTKit and CPU1 in an
+ *    SSE-200 both are present; CPU0 in an SSE-200 has neither.
+ *    Since the IoTKit has only one CPU, it does not have the CPU1_* properties.
  *  + Named GPIO inputs "EXP_IRQ" 0..n are the expansion interrupts for CPU 0,
  *    which are wired to its NVIC lines 32 .. n+32
  *  + Named GPIO inputs "EXP_CPU1_IRQ" 0..n are the expansion interrupts for
@@ -208,6 +213,8 @@ typedef struct ARMSSE {
     uint32_t mainclk_frq;
     uint32_t sram_addr_width;
     uint32_t init_svtor;
+    bool cpu_fpu[SSE_MAX_CPUS];
+    bool cpu_dsp[SSE_MAX_CPUS];
 } ARMSSE;
 
 typedef struct ARMSSEInfo ARMSSEInfo;