[Qemu-devel] qemu patch for adding functionality to rtas_ibm_get_system_parameter

[Tomohiro B Berry]

Hi all,

rtas_ibm_get_system_parameter did not previously have the functionality to 
return the appropriate string when called with the 
SPLPAR_CHARACTERISTICS_TOKEN.  I am proposing the following patch to add 
that functionality.  I am including the cases for 
CMO_CHARACTERISTICS_TOKEN and CEDE_LATENCY_TOKEN because the function gets 
called with those tokens during the boot process, but I understand that 
they are currently redundant with the default case.  I just figured they 
would be useful for future development, but if we don't want them in there 
right now I think that would be okay, too. 

Regards,
Tomo Berry

diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 1cb276d..318fdcd 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -225,6 +225,9 @@ static void rtas_stop_self(PowerPCCPU *cpu, 
sPAPREnvironment *spapr,
 }
 
 #define DIAGNOSTICS_RUN_MODE        42
+#define SPLPAR_CHARACTERISTICS_TOKEN 20
+#define CMO_CHARACTERISTICS_TOKEN 44
+#define CEDE_LATENCY_TOKEN 45
 
 static void rtas_ibm_get_system_parameter(PowerPCCPU *cpu,
                                           sPAPREnvironment *spapr,
@@ -236,6 +239,7 @@ static void rtas_ibm_get_system_parameter(PowerPCCPU 
*cpu,
     target_ulong buffer = rtas_ld(args, 1);
     target_ulong length = rtas_ld(args, 2);
     target_ulong ret = RTAS_OUT_NOT_SUPPORTED;
+    char *local_buffer;
 
     switch (parameter) {
     case DIAGNOSTICS_RUN_MODE:
@@ -244,6 +248,42 @@ static void rtas_ibm_get_system_parameter(PowerPCCPU 
*cpu,
             ret = RTAS_OUT_SUCCESS;
         }
         break;
+    case SPLPAR_CHARACTERISTICS_TOKEN:
+
+       /*  Create a string locally to copy to buffer  */
+ 
+       local_buffer=(char*)malloc(length*sizeof(char));
+       memset(local_buffer,0,length);
+
+       /*  These are the current system parameters supported.  The spaces 
at the 
+        *  start of the string are place holders for the string length. 
*/
+
+       snprintf(local_buffer,length," 
MaxEntCap=%d,MaxPlatProcs=%d",max_cpus,smp_cpus);
+
+       /*  The first 16 bits of the buffer must contain the length of the 
string.
+        *  These 16 bits are not included in the length of the string. */
+ 
+ 
((uint16_t*)local_buffer)[0]=cpu_to_be16((uint16_t)strlen(&local_buffer[2]));
+ 
+       /*  Copy the string into buffer using rtas_st_buffer to 
+        *  convert the addresses. */
+ 
+       rtas_st_buffer(buffer,length,(uint8_t*)local_buffer);
+
+       /*  Free the local buffer and return success. */ 
+ 
+       free(local_buffer);
+       ret = RTAS_OUT_SUCCESS;
+       break;
+    case CMO_CHARACTERISTICS_TOKEN:
+       ret = RTAS_OUT_NOT_SUPPORTED;
+       break;
+    case CEDE_LATENCY_TOKEN:
+       ret = RTAS_OUT_NOT_SUPPORTED;
+       break;
+    default:
+       ret = RTAS_OUT_NOT_SUPPORTED;
+       break;
     }
 
     rtas_st(rets, 0, ret);
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index b2f11e9..87c039c 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -356,6 +356,16 @@ static inline void rtas_st(target_ulong phys, int n, 
uint32_t val)
     stl_be_phys(ppc64_phys_to_real(phys + 4*n), val);
 }
 
+/*  This function will store a buffer 1 byte at a time into the 
+ *  address at phys up to a maximum of phys_len bytes. */
+
+static inline void rtas_st_buffer(target_ulong phys, target_ulong 
phys_len, uint8_t* buffer){
+    uint32_t i; 
+    for(i=0;i<phys_len;i++){
+        stb_phys(ppc64_phys_to_real(phys + i),buffer[i]);
+    }
+}
+
 typedef void (*spapr_rtas_fn)(PowerPCCPU *cpu, sPAPREnvironment *spapr,
                               uint32_t token,
                               uint32_t nargs, target_ulong args,
diff --git a/pixman b/pixman
--- a/pixman
+++ b/pixman
@@ -1 +1 @@
-Subproject commit 97336fad32acf802003855cd8bd6477fa49a12e3
+Subproject commit 97336fad32acf802003855cd8bd6477fa49a12e3-dirty