semihosting: add --semihosting-config arg sub-argument

Add new "arg" sub-argument to the --semihosting-config allowing the user
to pass multiple input arguments separately. It is required for example
by UHI semihosting to construct argc and argv.

Also, update ARM semihosting to support new option (at the moment it is
the only target which cares about arguments).

If the semihosting is enabled and no semihosting args have been specified,
then fall back to -kernel/-append. The -append string is split on whitespace
before initializing semihosting.argv[1..n]; this is different from what
QEMU MIPS machines' pseudo-bootloaders do (i.e. argv[1] contains the whole
-append), but is more intuitive from UHI user's point of view and Linux
kernel just does not care as it concatenates argv[1..n] into single cmdline
string anyway.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Message-id: 1434643256-16858-3-git-send-email-leon.alrae@imgtec.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 3 insertions, 7 deletions

diff --git a/target-arm/arm-semi.c b/target-arm/arm-semi.c
index a8b83e6..74a67e9 100644
--- a/target-arm/arm-semi.c
+++ b/target-arm/arm-semi.c
@@ -27,6 +27,7 @@
 #include <time.h>
 
 #include "cpu.h"
+#include "exec/semihost.h"
 #ifdef CONFIG_USER_ONLY
 #include "qemu.h"
 
@@ -440,10 +441,7 @@ uint32_t do_arm_semihosting(CPUARMState *env)
             input_size = arg1;
             /* Compute the size of the output string.  */
 #if !defined(CONFIG_USER_ONLY)
-            output_size = strlen(ts->boot_info->kernel_filename)
-                        + 1  /* Separating space.  */
-                        + strlen(ts->boot_info->kernel_cmdline)
-                        + 1; /* Terminating null byte.  */
+            output_size = strlen(semihosting_get_cmdline()) + 1;
 #else
             unsigned int i;
 
@@ -474,9 +472,7 @@ uint32_t do_arm_semihosting(CPUARMState *env)
 
             /* Copy the command-line arguments.  */
 #if !defined(CONFIG_USER_ONLY)
-            pstrcpy(output_buffer, output_size, ts->boot_info->kernel_filename);
-            pstrcat(output_buffer, output_size, " ");
-            pstrcat(output_buffer, output_size, ts->boot_info->kernel_cmdline);
+            pstrcpy(output_buffer, output_size, semihosting_get_cmdline());
 #else
             if (output_size == 1) {
                 /* Empty command-line.  */