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authorLinus Torvalds <torvalds@linux-foundation.org>2015-09-27 18:22:34 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-27 18:22:34 -0400
commit097f70b3c4d84ffccca15195bdfde3a37c0a7c0f (patch)
tree3338a83e351c980400bb524073b2bdfb5b0148be /arch/mips
parente3be4266d3488cbbaddf7fcc661f4473db341e46 (diff)
parente060f6ed281669b6d2f22d8dafd664b532386918 (diff)
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Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle: - Properly setup irq handling for ATH79 platforms - Fix bootmem mapstart calculation for contiguous maps - Handle little endian and older CPUs correct in BPF - Fix console for Fulong 2E systems - Handle FTLB correctly on R6 CPUs - Fixes for CM, GIC and MAAR support code * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: Initialise MAARs on secondary CPUs MIPS: print MAAR configuration during boot MIPS: mm: compile maar_init unconditionally irqchip: mips-gic: Fix pending & mask reads for MIPS64 with 32b GIC. irqchip: mips-gic: Convert CPU numbers to VP IDs. MIPS: CM: Provide a function to map from CPU to VP ID. MIPS: Fix FTLB detection for R6 MIPS: cpu-features: Add cpu_has_ftlb MIPS: ATH79: Add irq chip ar7240-misc-intc MIPS: ATH79: Set missing irq ack handler for ar7100-misc-intc irq chip MIPS: BPF: Fix build on pre-R2 little endian CPUs MIPS: BPF: Avoid unreachable code on little endian MIPS: bootmem: Fix mapstart calculation for contiguous maps MIPS: Fix console output for Fulong2e system
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/ath79/irq.c22
-rw-r--r--arch/mips/include/asm/cpu-features.h3
-rw-r--r--arch/mips/include/asm/cpu.h1
-rw-r--r--arch/mips/include/asm/maar.h9
-rw-r--r--arch/mips/include/asm/mips-cm.h39
-rw-r--r--arch/mips/include/asm/mipsregs.h2
-rw-r--r--arch/mips/kernel/cpu-probe.c21
-rw-r--r--arch/mips/kernel/setup.c10
-rw-r--r--arch/mips/kernel/smp.c2
-rw-r--r--arch/mips/loongson64/common/env.c3
-rw-r--r--arch/mips/mm/init.c177
-rw-r--r--arch/mips/net/bpf_jit_asm.S50
12 files changed, 262 insertions, 77 deletions
diff --git a/arch/mips/ath79/irq.c b/arch/mips/ath79/irq.c
index 15ecb4831e12..eeb3953ed8ac 100644
--- a/arch/mips/ath79/irq.c
+++ b/arch/mips/ath79/irq.c
@@ -293,8 +293,26 @@ static int __init ath79_misc_intc_of_init(
return 0;
}
-IRQCHIP_DECLARE(ath79_misc_intc, "qca,ar7100-misc-intc",
- ath79_misc_intc_of_init);
+
+static int __init ar7100_misc_intc_of_init(
+ struct device_node *node, struct device_node *parent)
+{
+ ath79_misc_irq_chip.irq_mask_ack = ar71xx_misc_irq_mask;
+ return ath79_misc_intc_of_init(node, parent);
+}
+
+IRQCHIP_DECLARE(ar7100_misc_intc, "qca,ar7100-misc-intc",
+ ar7100_misc_intc_of_init);
+
+static int __init ar7240_misc_intc_of_init(
+ struct device_node *node, struct device_node *parent)
+{
+ ath79_misc_irq_chip.irq_ack = ar724x_misc_irq_ack;
+ return ath79_misc_intc_of_init(node, parent);
+}
+
+IRQCHIP_DECLARE(ar7240_misc_intc, "qca,ar7240-misc-intc",
+ ar7240_misc_intc_of_init);
static int __init ar79_cpu_intc_of_init(
struct device_node *node, struct device_node *parent)
diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h
index 9801ac982655..fe67f12ac239 100644
--- a/arch/mips/include/asm/cpu-features.h
+++ b/arch/mips/include/asm/cpu-features.h
@@ -20,6 +20,9 @@
#ifndef cpu_has_tlb
#define cpu_has_tlb (cpu_data[0].options & MIPS_CPU_TLB)
#endif
+#ifndef cpu_has_ftlb
+#define cpu_has_ftlb (cpu_data[0].options & MIPS_CPU_FTLB)
+#endif
#ifndef cpu_has_tlbinv
#define cpu_has_tlbinv (cpu_data[0].options & MIPS_CPU_TLBINV)
#endif
diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index cd89e9855775..82ad15f11049 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -385,6 +385,7 @@ enum cpu_type_enum {
#define MIPS_CPU_CDMM 0x4000000000ull /* CPU has Common Device Memory Map */
#define MIPS_CPU_BP_GHIST 0x8000000000ull /* R12K+ Branch Prediction Global History */
#define MIPS_CPU_SP 0x10000000000ull /* Small (1KB) page support */
+#define MIPS_CPU_FTLB 0x20000000000ull /* CPU has Fixed-page-size TLB */
/*
* CPU ASE encodings
diff --git a/arch/mips/include/asm/maar.h b/arch/mips/include/asm/maar.h
index b02891f9caaf..21d9607c80d7 100644
--- a/arch/mips/include/asm/maar.h
+++ b/arch/mips/include/asm/maar.h
@@ -66,6 +66,15 @@ static inline void write_maar_pair(unsigned idx, phys_addr_t lower,
}
/**
+ * maar_init() - initialise MAARs
+ *
+ * Performs initialisation of MAARs for the current CPU, making use of the
+ * platforms implementation of platform_maar_init where necessary and
+ * duplicating the setup it provides on secondary CPUs.
+ */
+extern void maar_init(void);
+
+/**
* struct maar_config - MAAR configuration data
* @lower: The lowest address that the MAAR pair will affect. Must be
* aligned to a 2^16 byte boundary.
diff --git a/arch/mips/include/asm/mips-cm.h b/arch/mips/include/asm/mips-cm.h
index d75b75e78ebb..1f1927ab4269 100644
--- a/arch/mips/include/asm/mips-cm.h
+++ b/arch/mips/include/asm/mips-cm.h
@@ -194,6 +194,7 @@ BUILD_CM_RW(reg3_mask, MIPS_CM_GCB_OFS + 0xc8)
BUILD_CM_R_(gic_status, MIPS_CM_GCB_OFS + 0xd0)
BUILD_CM_R_(cpc_status, MIPS_CM_GCB_OFS + 0xf0)
BUILD_CM_RW(l2_config, MIPS_CM_GCB_OFS + 0x130)
+BUILD_CM_RW(sys_config2, MIPS_CM_GCB_OFS + 0x150)
/* Core Local & Core Other register accessor functions */
BUILD_CM_Cx_RW(reset_release, 0x00)
@@ -316,6 +317,10 @@ BUILD_CM_Cx_R_(tcid_8_priority, 0x80)
#define CM_GCR_L2_CONFIG_ASSOC_SHF 0
#define CM_GCR_L2_CONFIG_ASSOC_MSK (_ULCAST_(0xff) << 0)
+/* GCR_SYS_CONFIG2 register fields */
+#define CM_GCR_SYS_CONFIG2_MAXVPW_SHF 0
+#define CM_GCR_SYS_CONFIG2_MAXVPW_MSK (_ULCAST_(0xf) << 0)
+
/* GCR_Cx_COHERENCE register fields */
#define CM_GCR_Cx_COHERENCE_COHDOMAINEN_SHF 0
#define CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK (_ULCAST_(0xff) << 0)
@@ -405,4 +410,38 @@ static inline int mips_cm_revision(void)
return read_gcr_rev();
}
+/**
+ * mips_cm_max_vp_width() - return the width in bits of VP indices
+ *
+ * Return: the width, in bits, of VP indices in fields that combine core & VP
+ * indices.
+ */
+static inline unsigned int mips_cm_max_vp_width(void)
+{
+ extern int smp_num_siblings;
+
+ if (mips_cm_revision() >= CM_REV_CM3)
+ return read_gcr_sys_config2() & CM_GCR_SYS_CONFIG2_MAXVPW_MSK;
+
+ return smp_num_siblings;
+}
+
+/**
+ * mips_cm_vp_id() - calculate the hardware VP ID for a CPU
+ * @cpu: the CPU whose VP ID to calculate
+ *
+ * Hardware such as the GIC uses identifiers for VPs which may not match the
+ * CPU numbers used by Linux. This function calculates the hardware VP
+ * identifier corresponding to a given CPU.
+ *
+ * Return: the VP ID for the CPU.
+ */
+static inline unsigned int mips_cm_vp_id(unsigned int cpu)
+{
+ unsigned int core = cpu_data[cpu].core;
+ unsigned int vp = cpu_vpe_id(&cpu_data[cpu]);
+
+ return (core * mips_cm_max_vp_width()) + vp;
+}
+
#endif /* __MIPS_ASM_MIPS_CM_H__ */
diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index d3cd8eac81e3..c64781cf649f 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -487,6 +487,8 @@
/* Bits specific to the MIPS32/64 PRA. */
#define MIPS_CONF_MT (_ULCAST_(7) << 7)
+#define MIPS_CONF_MT_TLB (_ULCAST_(1) << 7)
+#define MIPS_CONF_MT_FTLB (_ULCAST_(4) << 7)
#define MIPS_CONF_AR (_ULCAST_(7) << 10)
#define MIPS_CONF_AT (_ULCAST_(3) << 13)
#define MIPS_CONF_M (_ULCAST_(1) << 31)
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 571a8e6ea5bd..09a51d091941 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -410,16 +410,18 @@ static int set_ftlb_enable(struct cpuinfo_mips *c, int enable)
static inline unsigned int decode_config0(struct cpuinfo_mips *c)
{
unsigned int config0;
- int isa;
+ int isa, mt;
config0 = read_c0_config();
/*
* Look for Standard TLB or Dual VTLB and FTLB
*/
- if ((((config0 & MIPS_CONF_MT) >> 7) == 1) ||
- (((config0 & MIPS_CONF_MT) >> 7) == 4))
+ mt = config0 & MIPS_CONF_MT;
+ if (mt == MIPS_CONF_MT_TLB)
c->options |= MIPS_CPU_TLB;
+ else if (mt == MIPS_CONF_MT_FTLB)
+ c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
isa = (config0 & MIPS_CONF_AT) >> 13;
switch (isa) {
@@ -559,15 +561,18 @@ static inline unsigned int decode_config4(struct cpuinfo_mips *c)
if (cpu_has_tlb) {
if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
c->options |= MIPS_CPU_TLBINV;
+
/*
- * This is a bit ugly. R6 has dropped that field from
- * config4 and the only valid configuration is VTLB+FTLB so
- * set a good value for mmuextdef for that case.
+ * R6 has dropped the MMUExtDef field from config4.
+ * On R6 the fields always describe the FTLB, and only if it is
+ * present according to Config.MT.
*/
- if (cpu_has_mips_r6)
+ if (!cpu_has_mips_r6)
+ mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
+ else if (cpu_has_ftlb)
mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
else
- mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
+ mmuextdef = 0;
switch (mmuextdef) {
case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 35b8316002f8..479515109e5b 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -338,7 +338,7 @@ static void __init bootmem_init(void)
if (end <= reserved_end)
continue;
#ifdef CONFIG_BLK_DEV_INITRD
- /* mapstart should be after initrd_end */
+ /* Skip zones before initrd and initrd itself */
if (initrd_end && end <= (unsigned long)PFN_UP(__pa(initrd_end)))
continue;
#endif
@@ -371,6 +371,14 @@ static void __init bootmem_init(void)
max_low_pfn = PFN_DOWN(HIGHMEM_START);
}
+#ifdef CONFIG_BLK_DEV_INITRD
+ /*
+ * mapstart should be after initrd_end
+ */
+ if (initrd_end)
+ mapstart = max(mapstart, (unsigned long)PFN_UP(__pa(initrd_end)));
+#endif
+
/*
* Initialize the boot-time allocator with low memory only.
*/
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index a31896c33716..bd4385a8e6e8 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -42,6 +42,7 @@
#include <asm/mmu_context.h>
#include <asm/time.h>
#include <asm/setup.h>
+#include <asm/maar.h>
cpumask_t cpu_callin_map; /* Bitmask of started secondaries */
@@ -157,6 +158,7 @@ asmlinkage void start_secondary(void)
mips_clockevent_init();
mp_ops->init_secondary();
cpu_report();
+ maar_init();
/*
* XXX parity protection should be folded in here when it's converted
diff --git a/arch/mips/loongson64/common/env.c b/arch/mips/loongson64/common/env.c
index f6c44dd332e2..d6d07ad56180 100644
--- a/arch/mips/loongson64/common/env.c
+++ b/arch/mips/loongson64/common/env.c
@@ -64,6 +64,9 @@ void __init prom_init_env(void)
}
if (memsize == 0)
memsize = 256;
+
+ loongson_sysconf.nr_uarts = 1;
+
pr_info("memsize=%u, highmemsize=%u\n", memsize, highmemsize);
#else
struct boot_params *boot_p;
diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index 66d0f49c5bec..8770e619185e 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -44,6 +44,7 @@
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <asm/fixmap.h>
+#include <asm/maar.h>
/*
* We have up to 8 empty zeroed pages so we can map one of the right colour
@@ -252,6 +253,119 @@ void __init fixrange_init(unsigned long start, unsigned long end,
#endif
}
+unsigned __weak platform_maar_init(unsigned num_pairs)
+{
+ struct maar_config cfg[BOOT_MEM_MAP_MAX];
+ unsigned i, num_configured, num_cfg = 0;
+ phys_addr_t skip;
+
+ for (i = 0; i < boot_mem_map.nr_map; i++) {
+ switch (boot_mem_map.map[i].type) {
+ case BOOT_MEM_RAM:
+ case BOOT_MEM_INIT_RAM:
+ break;
+ default:
+ continue;
+ }
+
+ skip = 0x10000 - (boot_mem_map.map[i].addr & 0xffff);
+
+ cfg[num_cfg].lower = boot_mem_map.map[i].addr;
+ cfg[num_cfg].lower += skip;
+
+ cfg[num_cfg].upper = cfg[num_cfg].lower;
+ cfg[num_cfg].upper += boot_mem_map.map[i].size - 1;
+ cfg[num_cfg].upper -= skip;
+
+ cfg[num_cfg].attrs = MIPS_MAAR_S;
+ num_cfg++;
+ }
+
+ num_configured = maar_config(cfg, num_cfg, num_pairs);
+ if (num_configured < num_cfg)
+ pr_warn("Not enough MAAR pairs (%u) for all bootmem regions (%u)\n",
+ num_pairs, num_cfg);
+
+ return num_configured;
+}
+
+void maar_init(void)
+{
+ unsigned num_maars, used, i;
+ phys_addr_t lower, upper, attr;
+ static struct {
+ struct maar_config cfgs[3];
+ unsigned used;
+ } recorded = { { { 0 } }, 0 };
+
+ if (!cpu_has_maar)
+ return;
+
+ /* Detect the number of MAARs */
+ write_c0_maari(~0);
+ back_to_back_c0_hazard();
+ num_maars = read_c0_maari() + 1;
+
+ /* MAARs should be in pairs */
+ WARN_ON(num_maars % 2);
+
+ /* Set MAARs using values we recorded already */
+ if (recorded.used) {
+ used = maar_config(recorded.cfgs, recorded.used, num_maars / 2);
+ BUG_ON(used != recorded.used);
+ } else {
+ /* Configure the required MAARs */
+ used = platform_maar_init(num_maars / 2);
+ }
+
+ /* Disable any further MAARs */
+ for (i = (used * 2); i < num_maars; i++) {
+ write_c0_maari(i);
+ back_to_back_c0_hazard();
+ write_c0_maar(0);
+ back_to_back_c0_hazard();
+ }
+
+ if (recorded.used)
+ return;
+
+ pr_info("MAAR configuration:\n");
+ for (i = 0; i < num_maars; i += 2) {
+ write_c0_maari(i);
+ back_to_back_c0_hazard();
+ upper = read_c0_maar();
+
+ write_c0_maari(i + 1);
+ back_to_back_c0_hazard();
+ lower = read_c0_maar();
+
+ attr = lower & upper;
+ lower = (lower & MIPS_MAAR_ADDR) << 4;
+ upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff;
+
+ pr_info(" [%d]: ", i / 2);
+ if (!(attr & MIPS_MAAR_V)) {
+ pr_cont("disabled\n");
+ continue;
+ }
+
+ pr_cont("%pa-%pa", &lower, &upper);
+
+ if (attr & MIPS_MAAR_S)
+ pr_cont(" speculate");
+
+ pr_cont("\n");
+
+ /* Record the setup for use on secondary CPUs */
+ if (used <= ARRAY_SIZE(recorded.cfgs)) {
+ recorded.cfgs[recorded.used].lower = lower;
+ recorded.cfgs[recorded.used].upper = upper;
+ recorded.cfgs[recorded.used].attrs = attr;
+ recorded.used++;
+ }
+ }
+}
+
#ifndef CONFIG_NEED_MULTIPLE_NODES
int page_is_ram(unsigned long pagenr)
{
@@ -334,69 +448,6 @@ static inline void mem_init_free_highmem(void)
#endif
}
-unsigned __weak platform_maar_init(unsigned num_pairs)
-{
- struct maar_config cfg[BOOT_MEM_MAP_MAX];
- unsigned i, num_configured, num_cfg = 0;
- phys_addr_t skip;
-
- for (i = 0; i < boot_mem_map.nr_map; i++) {
- switch (boot_mem_map.map[i].type) {
- case BOOT_MEM_RAM:
- case BOOT_MEM_INIT_RAM:
- break;
- default:
- continue;
- }
-
- skip = 0x10000 - (boot_mem_map.map[i].addr & 0xffff);
-
- cfg[num_cfg].lower = boot_mem_map.map[i].addr;
- cfg[num_cfg].lower += skip;
-
- cfg[num_cfg].upper = cfg[num_cfg].lower;
- cfg[num_cfg].upper += boot_mem_map.map[i].size - 1;
- cfg[num_cfg].upper -= skip;
-
- cfg[num_cfg].attrs = MIPS_MAAR_S;
- num_cfg++;
- }
-
- num_configured = maar_config(cfg, num_cfg, num_pairs);
- if (num_configured < num_cfg)
- pr_warn("Not enough MAAR pairs (%u) for all bootmem regions (%u)\n",
- num_pairs, num_cfg);
-
- return num_configured;
-}
-
-static void maar_init(void)
-{
- unsigned num_maars, used, i;
-
- if (!cpu_has_maar)
- return;
-
- /* Detect the number of MAARs */
- write_c0_maari(~0);
- back_to_back_c0_hazard();
- num_maars = read_c0_maari() + 1;
-
- /* MAARs should be in pairs */
- WARN_ON(num_maars % 2);
-
- /* Configure the required MAARs */
- used = platform_maar_init(num_maars / 2);
-
- /* Disable any further MAARs */
- for (i = (used * 2); i < num_maars; i++) {
- write_c0_maari(i);
- back_to_back_c0_hazard();
- write_c0_maar(0);
- back_to_back_c0_hazard();
- }
-}
-
void __init mem_init(void)
{
#ifdef CONFIG_HIGHMEM
diff --git a/arch/mips/net/bpf_jit_asm.S b/arch/mips/net/bpf_jit_asm.S
index e92726099be0..dabf4179cd7e 100644
--- a/arch/mips/net/bpf_jit_asm.S
+++ b/arch/mips/net/bpf_jit_asm.S
@@ -64,8 +64,20 @@ sk_load_word_positive:
PTR_ADDU t1, $r_skb_data, offset
lw $r_A, 0(t1)
#ifdef CONFIG_CPU_LITTLE_ENDIAN
+# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
wsbh t0, $r_A
rotr $r_A, t0, 16
+# else
+ sll t0, $r_A, 24
+ srl t1, $r_A, 24
+ srl t2, $r_A, 8
+ or t0, t0, t1
+ andi t2, t2, 0xff00
+ andi t1, $r_A, 0xff00
+ or t0, t0, t2
+ sll t1, t1, 8
+ or $r_A, t0, t1
+# endif
#endif
jr $r_ra
move $r_ret, zero
@@ -80,8 +92,16 @@ sk_load_half_positive:
PTR_ADDU t1, $r_skb_data, offset
lh $r_A, 0(t1)
#ifdef CONFIG_CPU_LITTLE_ENDIAN
+# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
wsbh t0, $r_A
seh $r_A, t0
+# else
+ sll t0, $r_A, 24
+ andi t1, $r_A, 0xff00
+ sra t0, t0, 16
+ srl t1, t1, 8
+ or $r_A, t0, t1
+# endif
#endif
jr $r_ra
move $r_ret, zero
@@ -148,23 +168,47 @@ sk_load_byte_positive:
NESTED(bpf_slow_path_word, (6 * SZREG), $r_sp)
bpf_slow_path_common(4)
#ifdef CONFIG_CPU_LITTLE_ENDIAN
+# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
wsbh t0, $r_s0
jr $r_ra
rotr $r_A, t0, 16
-#endif
+# else
+ sll t0, $r_s0, 24
+ srl t1, $r_s0, 24
+ srl t2, $r_s0, 8
+ or t0, t0, t1
+ andi t2, t2, 0xff00
+ andi t1, $r_s0, 0xff00
+ or t0, t0, t2
+ sll t1, t1, 8
+ jr $r_ra
+ or $r_A, t0, t1
+# endif
+#else
jr $r_ra
- move $r_A, $r_s0
+ move $r_A, $r_s0
+#endif
END(bpf_slow_path_word)
NESTED(bpf_slow_path_half, (6 * SZREG), $r_sp)
bpf_slow_path_common(2)
#ifdef CONFIG_CPU_LITTLE_ENDIAN
+# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
jr $r_ra
wsbh $r_A, $r_s0
-#endif
+# else
+ sll t0, $r_s0, 8
+ andi t1, $r_s0, 0xff00
+ andi t0, t0, 0xff00
+ srl t1, t1, 8
+ jr $r_ra
+ or $r_A, t0, t1
+# endif
+#else
jr $r_ra
move $r_A, $r_s0
+#endif
END(bpf_slow_path_half)