ARCv2: spinlock/rwlock/atomics: Delayed retry of failed SCOND with exponential backoff

[cascardo/linux.git] / arch / arc / kernel / setup.c

diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index a3d1862..cabde9d 100644 (file)
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -47,6 +47,7 @@ static void read_arc_build_cfg_regs(void)
        struct bcr_perip uncached_space;
        struct bcr_generic bcr;
        struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
+       unsigned long perip_space;
        FIX_PTR(cpu);
 
        READ_BCR(AUX_IDENTITY, cpu->core);
@@ -56,7 +57,12 @@ static void read_arc_build_cfg_regs(void)
        cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
 
        READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
-       BUG_ON((uncached_space.start << 24) != ARC_UNCACHED_ADDR_SPACE);
+        if (uncached_space.ver < 3)
+               perip_space = uncached_space.start << 24;
+       else
+               perip_space = read_aux_reg(AUX_NON_VOL) & 0xF0000000;
+
+       BUG_ON(perip_space != ARC_UNCACHED_ADDR_SPACE);
 
        READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
 
@@ -142,17 +148,22 @@ static void read_arc_build_cfg_regs(void)
 }
 
 static const struct cpuinfo_data arc_cpu_tbl[] = {
+#ifdef CONFIG_ISA_ARCOMPACT
        { {0x20, "ARC 600"      }, 0x2F},
        { {0x30, "ARC 700"      }, 0x33},
        { {0x34, "ARC 700 R4.10"}, 0x34},
        { {0x35, "ARC 700 R4.11"}, 0x35},
-       { {0x50, "ARC HS38"     }, 0x51},
+#else
+       { {0x50, "ARC HS38 R2.0"}, 0x51},
+       { {0x52, "ARC HS38 R2.1"}, 0x52},
+#endif
        { {0x00, NULL           } }
 };
 
-#define IS_AVAIL1(v, str)      ((v) ? str : "")
-#define IS_USED(cfg)           (IS_ENABLED(cfg) ? "" : "(not used) ")
-#define IS_AVAIL2(v, str, cfg)  IS_AVAIL1(v, str), IS_AVAIL1(v, IS_USED(cfg))
+#define IS_AVAIL1(v, s)                ((v) ? s : "")
+#define IS_USED_RUN(v)         ((v) ? "" : "(not used) ")
+#define IS_USED_CFG(cfg)       IS_USED_RUN(IS_ENABLED(cfg))
+#define IS_AVAIL2(v, s, cfg)   IS_AVAIL1(v, s), IS_AVAIL1(v, IS_USED_CFG(cfg))
 
 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 {
@@ -226,7 +237,7 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
                        n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
                }
                n += scnprintf(buf + n, len - n, "%s",
-                              IS_USED(CONFIG_ARC_HAS_HW_MPY));
+                              IS_USED_CFG(CONFIG_ARC_HAS_HW_MPY));
        }
 
        n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
@@ -325,6 +336,10 @@ static void arc_chk_core_config(void)
                pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
        else if (!cpu->extn.fpu_dp && fpu_enabled)
                panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
+
+       if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic &&
+           !IS_ENABLED(CONFIG_ARC_STAR_9000923308))
+               panic("llock/scond livelock workaround missing\n");
 }
 
 /*