Re: [Qemu-devel] [QEMU-PPC] [PATCH V3 6/6] target/ppc/spapr: Add H-Call H_GET_CPU_CHARACTERISTICS

[David Gibson]

On Mon, Jan 15, 2018 at 05:32:35PM +1100, Suraj Jitindar Singh wrote:
> The new H-Call H_GET_CPU_CHARACTERISTICS is used by the guest to query
> behaviours and available characteristics of the cpu.
> 
> Implement the handler for this new H-Call which formulates its response
> based on the setting of the spapr_caps cap-cfpc, cap-sbbc and cap-ibs.
> 
> Signed-off-by: Suraj Jitindar Singh 
> ---
>  hw/ppc/spapr_hcall.c   | 66 
> ++
>  include/hw/ppc/spapr.h |  1 +
>  2 files changed, 67 insertions(+)
> 
> diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> index 51eba52e86..a693d3b852 100644
> --- a/hw/ppc/spapr_hcall.c
> +++ b/hw/ppc/spapr_hcall.c
> @@ -1654,6 +1654,69 @@ static target_ulong 
> h_client_architecture_support(PowerPCCPU *cpu,
>  return H_SUCCESS;
>  }
>  
> +static target_ulong h_get_cpu_characteristics(PowerPCCPU *cpu,
> +  sPAPRMachineState *spapr,
> +  target_ulong opcode,
> +  target_ulong *args)
> +{
> +uint64_t characteristics = H_CPU_CHAR_HON_BRANCH_HINTS &
> +~H_CPU_CHAR_THR_RECONF_TRIG;
> +uint64_t behaviour = H_CPU_BEHAV_FAVOUR_SECURITY;
> +uint8_t safe_cache = spapr_get_cap(spapr, SPAPR_CAP_CFPC);
> +uint8_t safe_bounds_check = spapr_get_cap(spapr, SPAPR_CAP_SBBC);
> +uint8_t safe_indirect_branch = spapr_get_cap(spapr, SPAPR_CAP_IBS);
> +
> +switch (safe_cache) {
> +case SPAPR_CAP_WORKAROUND:
> +characteristics |= H_CPU_CHAR_L1D_FLUSH_ORI30;
> +characteristics |= H_CPU_CHAR_L1D_FLUSH_TRIG2;
> +characteristics |= H_CPU_CHAR_L1D_THREAD_PRIV;
> +behaviour |= H_CPU_BEHAV_L1D_FLUSH_PR;
> +break;
> +case SPAPR_CAP_FIXED:
> +break;
> +default: /* broken */
> +if (safe_cache != SPAPR_CAP_BROKEN) {

I think you just assert() for this.  The only way these could get a
different value is if there's a bug elsewhere.

> +error_report("Invalid value for cap-cfpc (%d), assuming broken",
> + safe_cache);
> +}
> +behaviour |= H_CPU_BEHAV_L1D_FLUSH_PR;
> +break;
> +}
> +
> +switch (safe_bounds_check) {
> +case SPAPR_CAP_WORKAROUND:
> +characteristics |= H_CPU_CHAR_SPEC_BAR_ORI31;
> +behaviour |= H_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
> +break;
> +case SPAPR_CAP_FIXED:
> +break;
> +default: /* broken */
> +if (safe_bounds_check != SPAPR_CAP_BROKEN) {
> +error_report("Invalid value for cap-sbbc (%d), assuming broken",
> + safe_bounds_check);
> +}
> +behaviour |= H_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
> +break;
> +}
> +
> +switch (safe_indirect_branch) {
> +case SPAPR_CAP_FIXED:
> +characteristics |= H_CPU_CHAR_BCCTRL_SERIALISED;
> +default: /* broken */
> +if (safe_indirect_branch != SPAPR_CAP_BROKEN) {
> +error_report("Invalid value for cap-ibs (%d), assuming broken",
> + safe_indirect_branch);
> +}
> +break;
> +}
> +
> +args[0] = characteristics;
> +args[1] = behaviour;
> +
> +return H_SUCCESS;
> +}
> +
>  static spapr_hcall_fn papr_hypercall_table[(MAX_HCALL_OPCODE / 4) + 1];
>  static spapr_hcall_fn kvmppc_hypercall_table[KVMPPC_HCALL_MAX - 
> KVMPPC_HCALL_BASE + 1];
>  
> @@ -1733,6 +1796,9 @@ static void hypercall_register_types(void)
>  spapr_register_hypercall(H_INVALIDATE_PID, h_invalidate_pid);
>  spapr_register_hypercall(H_REGISTER_PROC_TBL, h_register_process_table);
>  
> +/* hcall-get-cpu-characteristics */
> +spapr_register_hypercall(H_GET_CPU_CHARACTERISTICS, 
> h_get_cpu_characteristics);
> +
>  /* "debugger" hcalls (also used by SLOF). Note: We do -not- differenciate
>   * here between the "CI" and the "CACHE" variants, they will use whatever
>   * mapping attributes qemu is using. When using KVM, the kernel will
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 549d7a4134..62c077ac20 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -404,6 +404,7 @@ struct sPAPRMachineState {
>  #define H_GET_HCA_INFO  0x1B8
>  #define H_GET_PERF_COUNT0x1BC
>  #define H_MANAGE_TRACE  0x1C0
> +#define H_GET_CPU_CHARACTERISTICS 0x1C8
>  #define H_FREE_LOGICAL_LAN_BUFFER 0x1D4
>  #define H_QUERY_INT_STATE   0x1E4
>  #define H_POLL_PENDING  0x1D8

-- 
David Gibson| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson


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[Qemu-devel] [QEMU-PPC] [PATCH V3 6/6] target/ppc/spapr: Add H-Call H_GET_CPU_CHARACTERISTICS

[Suraj Jitindar Singh]

The new H-Call H_GET_CPU_CHARACTERISTICS is used by the guest to query
behaviours and available characteristics of the cpu.

Implement the handler for this new H-Call which formulates its response
based on the setting of the spapr_caps cap-cfpc, cap-sbbc and cap-ibs.

Signed-off-by: Suraj Jitindar Singh 
---
 hw/ppc/spapr_hcall.c   | 66 ++
 include/hw/ppc/spapr.h |  1 +
 2 files changed, 67 insertions(+)

diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
index 51eba52e86..a693d3b852 100644
--- a/hw/ppc/spapr_hcall.c
+++ b/hw/ppc/spapr_hcall.c
@@ -1654,6 +1654,69 @@ static target_ulong 
h_client_architecture_support(PowerPCCPU *cpu,
 return H_SUCCESS;
 }
 
+static target_ulong h_get_cpu_characteristics(PowerPCCPU *cpu,
+  sPAPRMachineState *spapr,
+  target_ulong opcode,
+  target_ulong *args)
+{
+uint64_t characteristics = H_CPU_CHAR_HON_BRANCH_HINTS &
+  ~H_CPU_CHAR_THR_RECONF_TRIG;
+uint64_t behaviour = H_CPU_BEHAV_FAVOUR_SECURITY;
+uint8_t safe_cache = spapr_get_cap(spapr, SPAPR_CAP_CFPC);
+uint8_t safe_bounds_check = spapr_get_cap(spapr, SPAPR_CAP_SBBC);
+uint8_t safe_indirect_branch = spapr_get_cap(spapr, SPAPR_CAP_IBS);
+
+switch (safe_cache) {
+case SPAPR_CAP_WORKAROUND:
+characteristics |= H_CPU_CHAR_L1D_FLUSH_ORI30;
+characteristics |= H_CPU_CHAR_L1D_FLUSH_TRIG2;
+characteristics |= H_CPU_CHAR_L1D_THREAD_PRIV;
+behaviour |= H_CPU_BEHAV_L1D_FLUSH_PR;
+break;
+case SPAPR_CAP_FIXED:
+break;
+default: /* broken */
+if (safe_cache != SPAPR_CAP_BROKEN) {
+error_report("Invalid value for cap-cfpc (%d), assuming broken",
+ safe_cache);
+}
+behaviour |= H_CPU_BEHAV_L1D_FLUSH_PR;
+break;
+}
+
+switch (safe_bounds_check) {
+case SPAPR_CAP_WORKAROUND:
+characteristics |= H_CPU_CHAR_SPEC_BAR_ORI31;
+behaviour |= H_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
+break;
+case SPAPR_CAP_FIXED:
+break;
+default: /* broken */
+if (safe_bounds_check != SPAPR_CAP_BROKEN) {
+error_report("Invalid value for cap-sbbc (%d), assuming broken",
+ safe_bounds_check);
+}
+behaviour |= H_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
+break;
+}
+
+switch (safe_indirect_branch) {
+case SPAPR_CAP_FIXED:
+characteristics |= H_CPU_CHAR_BCCTRL_SERIALISED;
+default: /* broken */
+if (safe_indirect_branch != SPAPR_CAP_BROKEN) {
+error_report("Invalid value for cap-ibs (%d), assuming broken",
+ safe_indirect_branch);
+}
+break;
+}
+
+args[0] = characteristics;
+args[1] = behaviour;
+
+return H_SUCCESS;
+}
+
 static spapr_hcall_fn papr_hypercall_table[(MAX_HCALL_OPCODE / 4) + 1];
 static spapr_hcall_fn kvmppc_hypercall_table[KVMPPC_HCALL_MAX - 
KVMPPC_HCALL_BASE + 1];
 
@@ -1733,6 +1796,9 @@ static void hypercall_register_types(void)
 spapr_register_hypercall(H_INVALIDATE_PID, h_invalidate_pid);
 spapr_register_hypercall(H_REGISTER_PROC_TBL, h_register_process_table);
 
+/* hcall-get-cpu-characteristics */
+spapr_register_hypercall(H_GET_CPU_CHARACTERISTICS, 
h_get_cpu_characteristics);
+
 /* "debugger" hcalls (also used by SLOF). Note: We do -not- differenciate
  * here between the "CI" and the "CACHE" variants, they will use whatever
  * mapping attributes qemu is using. When using KVM, the kernel will
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 549d7a4134..62c077ac20 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -404,6 +404,7 @@ struct sPAPRMachineState {
 #define H_GET_HCA_INFO  0x1B8
 #define H_GET_PERF_COUNT0x1BC
 #define H_MANAGE_TRACE  0x1C0
+#define H_GET_CPU_CHARACTERISTICS 0x1C8
 #define H_FREE_LOGICAL_LAN_BUFFER 0x1D4
 #define H_QUERY_INT_STATE   0x1E4
 #define H_POLL_PENDING  0x1D8
-- 
2.13.6