target/ppc: Work [S]PURR implementation and add HV support

The Processor Utilisation of Resources Register (PURR) and Scaled
Processor Utilisation of Resources Register (SPURR) provide an estimate
of the resources used by the thread, present on POWER7 and later
processors.

Currently the [S]PURR registers simply count at the rate of the
timebase.

Preserve this behaviour but rework the implementation to store an offset
like the timebase rather than doing the calculation manually. Also allow
hypervisor write access to the register along with the currently
available read access.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[ clg: rebased on current ppc tree ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20191128134700.16091-3-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c
index d8c402811fd75700699841a7e4b0ab7397ce72ec..2856d694959bd853fab62a5d8b0098fa90bcbf0f 100644 (file)
--- a/hw/ppc/ppc.c
+++ b/hw/ppc/ppc.c
@@ -809,12 +809,9 @@ target_ulong cpu_ppc_load_hdecr(CPUPPCState *env)
 uint64_t cpu_ppc_load_purr (CPUPPCState *env)
 {
     ppc_tb_t *tb_env = env->tb_env;
-    uint64_t diff;
 
-    diff = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - tb_env->purr_start;
-
-    return tb_env->purr_load +
-        muldiv64(diff, tb_env->tb_freq, NANOSECONDS_PER_SECOND);
+    return cpu_ppc_get_tb(tb_env, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL),
+                          tb_env->purr_offset);
 }
 
 /* When decrementer expires,
@@ -973,12 +970,12 @@ static void cpu_ppc_hdecr_cb(void *opaque)
     cpu_ppc_hdecr_excp(cpu);
 }
 
-static void cpu_ppc_store_purr(PowerPCCPU *cpu, uint64_t value)
+void cpu_ppc_store_purr(CPUPPCState *env, uint64_t value)
 {
-    ppc_tb_t *tb_env = cpu->env.tb_env;
+    ppc_tb_t *tb_env = env->tb_env;
 
-    tb_env->purr_load = value;
-    tb_env->purr_start = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    cpu_ppc_store_tb(tb_env, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL),
+                     &tb_env->purr_offset, value);
 }
 
 static void cpu_ppc_set_tb_clk (void *opaque, uint32_t freq)
@@ -995,7 +992,7 @@ static void cpu_ppc_set_tb_clk (void *opaque, uint32_t freq)
      */
     _cpu_ppc_store_decr(cpu, 0xFFFFFFFF, 0xFFFFFFFF, 32);
     _cpu_ppc_store_hdecr(cpu, 0xFFFFFFFF, 0xFFFFFFFF, 32);
-    cpu_ppc_store_purr(cpu, 0x0000000000000000ULL);
+    cpu_ppc_store_purr(env, 0x0000000000000000ULL);
 }
 
 static void timebase_save(PPCTimebase *tb)

diff --git a/include/hw/ppc/ppc.h b/include/hw/ppc/ppc.h
index d7a95608f6e457c45ccf10d737ee74aac79c4b2d..4ea5436095778f0d7117ce6d3469c71e58489c6a 100644 (file)
--- a/include/hw/ppc/ppc.h
+++ b/include/hw/ppc/ppc.h
@@ -33,8 +33,7 @@ struct ppc_tb_t {
     /* Hypervisor decrementer management */
     uint64_t hdecr_next;    /* Tick for next hdecr interrupt  */
     QEMUTimer *hdecr_timer;
-    uint64_t purr_load;
-    uint64_t purr_start;
+    int64_t purr_offset;
     void *opaque;
     uint32_t flags;
 };

diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index eb7d2c76378569556ff0374dddb8d1ace1fdfaa6..da44cc8809adafb5e2737445f0cdaf23c17eed52 100644 (file)
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -1311,6 +1311,7 @@ void cpu_ppc_store_decr(CPUPPCState *env, target_ulong value);
 target_ulong cpu_ppc_load_hdecr(CPUPPCState *env);
 void cpu_ppc_store_hdecr(CPUPPCState *env, target_ulong value);
 uint64_t cpu_ppc_load_purr(CPUPPCState *env);
+void cpu_ppc_store_purr(CPUPPCState *env, uint64_t value);
 uint32_t cpu_ppc601_load_rtcl(CPUPPCState *env);
 uint32_t cpu_ppc601_load_rtcu(CPUPPCState *env);
 #if !defined(CONFIG_USER_ONLY)

diff --git a/target/ppc/helper.h b/target/ppc/helper.h
index a5f53bb421a7cd6bed5b8c5d9b2c1db02db297b0..356a14d8a6390130a174f1f06188d1b33d1d7b81 100644 (file)
--- a/target/ppc/helper.h
+++ b/target/ppc/helper.h
@@ -655,6 +655,7 @@ DEF_HELPER_FLAGS_1(load_601_rtcu, TCG_CALL_NO_RWG, tl, env)
 #if !defined(CONFIG_USER_ONLY)
 #if defined(TARGET_PPC64)
 DEF_HELPER_FLAGS_1(load_purr, TCG_CALL_NO_RWG, tl, env)
+DEF_HELPER_FLAGS_2(store_purr, TCG_CALL_NO_RWG, void, env, tl)
 DEF_HELPER_2(store_ptcr, void, env, tl)
 #endif
 DEF_HELPER_2(store_sdr1, void, env, tl)

diff --git a/target/ppc/timebase_helper.c b/target/ppc/timebase_helper.c
index 8c3c2fe67c2cc5705d6fe8f5fb989afe7912012e..2395295b778c2a435aba172371d6cf7312c1db91 100644 (file)
--- a/target/ppc/timebase_helper.c
+++ b/target/ppc/timebase_helper.c
@@ -55,6 +55,11 @@ target_ulong helper_load_purr(CPUPPCState *env)
 {
     return (target_ulong)cpu_ppc_load_purr(env);
 }
+
+void helper_store_purr(CPUPPCState *env, target_ulong val)
+{
+    cpu_ppc_store_purr(env, val);
+}
 #endif
 
 target_ulong helper_load_601_rtcl(CPUPPCState *env)

diff --git a/target/ppc/translate_init.inc.c b/target/ppc/translate_init.inc.c
index 226aecf8f486125d38092ff4e58f10a8f77d956e..c5e4d45569550adf556135d09f2c2b16aa65f6e6 100644 (file)
--- a/target/ppc/translate_init.inc.c
+++ b/target/ppc/translate_init.inc.c
@@ -287,6 +287,11 @@ static void spr_read_purr(DisasContext *ctx, int gprn, int sprn)
     gen_helper_load_purr(cpu_gpr[gprn], cpu_env);
 }
 
+static void spr_write_purr(DisasContext *ctx, int sprn, int gprn)
+{
+    gen_helper_store_purr(cpu_env, cpu_gpr[gprn]);
+}
+
 /* HDECR */
 static void spr_read_hdecr(DisasContext *ctx, int gprn, int sprn)
 {
@@ -8013,14 +8018,16 @@ static void gen_spr_book3s_purr(CPUPPCState *env)
 {
 #if !defined(CONFIG_USER_ONLY)
     /* PURR & SPURR: Hack - treat these as aliases for the TB for now */
-    spr_register_kvm(env, SPR_PURR,   "PURR",
-                     &spr_read_purr, SPR_NOACCESS,
-                     &spr_read_purr, SPR_NOACCESS,
-                     KVM_REG_PPC_PURR, 0x00000000);
-    spr_register_kvm(env, SPR_SPURR,   "SPURR",
-                     &spr_read_purr, SPR_NOACCESS,
-                     &spr_read_purr, SPR_NOACCESS,
-                     KVM_REG_PPC_SPURR, 0x00000000);
+    spr_register_kvm_hv(env, SPR_PURR,   "PURR",
+                        &spr_read_purr, SPR_NOACCESS,
+                        &spr_read_purr, SPR_NOACCESS,
+                        &spr_read_purr, &spr_write_purr,
+                        KVM_REG_PPC_PURR, 0x00000000);
+    spr_register_kvm_hv(env, SPR_SPURR,   "SPURR",
+                        &spr_read_purr, SPR_NOACCESS,
+                        &spr_read_purr, SPR_NOACCESS,
+                        &spr_read_purr, &spr_write_purr,
+                        KVM_REG_PPC_SPURR, 0x00000000);
 #endif
 }