summaryrefslogtreecommitdiffstats
path: root/arch/mips
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/Kconfig15
-rw-r--r--arch/mips/boot/dts/ingenic/ci20.dts8
-rw-r--r--arch/mips/boot/dts/ingenic/jz4740.dtsi2
-rw-r--r--arch/mips/boot/dts/xilfpga/nexys4ddr.dts8
-rw-r--r--arch/mips/include/asm/atomic.h6
-rw-r--r--arch/mips/include/asm/barrier.h36
-rw-r--r--arch/mips/include/asm/bitops.h5
-rw-r--r--arch/mips/include/asm/futex.h3
-rw-r--r--arch/mips/include/asm/pgtable.h2
-rw-r--r--arch/mips/kernel/mips-cm.c2
-rw-r--r--arch/mips/kernel/process.c7
-rw-r--r--arch/mips/loongson64/Platform23
-rw-r--r--arch/mips/loongson64/common/reset.c7
-rw-r--r--arch/mips/mm/tlbex.c10
-rw-r--r--arch/mips/pci/pci-octeon.c10
-rw-r--r--arch/mips/vdso/Makefile5
16 files changed, 127 insertions, 22 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 0d14f51d0002..a84c24d894aa 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1403,6 +1403,21 @@ config LOONGSON3_ENHANCEMENT
please say 'N' here. If you want a high-performance kernel to run on
new Loongson 3 machines only, please say 'Y' here.
+config CPU_LOONGSON3_WORKAROUNDS
+ bool "Old Loongson 3 LLSC Workarounds"
+ default y if SMP
+ depends on CPU_LOONGSON3
+ help
+ Loongson 3 processors have the llsc issues which require workarounds.
+ Without workarounds the system may hang unexpectedly.
+
+ Newer Loongson 3 will fix these issues and no workarounds are needed.
+ The workarounds have no significant side effect on them but may
+ decrease the performance of the system so this option should be
+ disabled unless the kernel is intended to be run on old systems.
+
+ If unsure, please say Y.
+
config CPU_LOONGSON2E
bool "Loongson 2E"
depends on SYS_HAS_CPU_LOONGSON2E
diff --git a/arch/mips/boot/dts/ingenic/ci20.dts b/arch/mips/boot/dts/ingenic/ci20.dts
index 50cff3cbcc6d..4f7b1fa31cf5 100644
--- a/arch/mips/boot/dts/ingenic/ci20.dts
+++ b/arch/mips/boot/dts/ingenic/ci20.dts
@@ -76,7 +76,7 @@
status = "okay";
pinctrl-names = "default";
- pinctrl-0 = <&pins_uart2>;
+ pinctrl-0 = <&pins_uart3>;
};
&uart4 {
@@ -196,9 +196,9 @@
bias-disable;
};
- pins_uart2: uart2 {
- function = "uart2";
- groups = "uart2-data", "uart2-hwflow";
+ pins_uart3: uart3 {
+ function = "uart3";
+ groups = "uart3-data", "uart3-hwflow";
bias-disable;
};
diff --git a/arch/mips/boot/dts/ingenic/jz4740.dtsi b/arch/mips/boot/dts/ingenic/jz4740.dtsi
index 6fb16fd24035..2beb78a62b7d 100644
--- a/arch/mips/boot/dts/ingenic/jz4740.dtsi
+++ b/arch/mips/boot/dts/ingenic/jz4740.dtsi
@@ -161,7 +161,7 @@
#dma-cells = <2>;
interrupt-parent = <&intc>;
- interrupts = <29>;
+ interrupts = <20>;
clocks = <&cgu JZ4740_CLK_DMA>;
diff --git a/arch/mips/boot/dts/xilfpga/nexys4ddr.dts b/arch/mips/boot/dts/xilfpga/nexys4ddr.dts
index 2152b7ba65fb..cc8dbea0911f 100644
--- a/arch/mips/boot/dts/xilfpga/nexys4ddr.dts
+++ b/arch/mips/boot/dts/xilfpga/nexys4ddr.dts
@@ -90,11 +90,11 @@
interrupts = <0>;
};
- axi_i2c: i2c@10A00000 {
+ axi_i2c: i2c@10a00000 {
compatible = "xlnx,xps-iic-2.00.a";
interrupt-parent = <&axi_intc>;
interrupts = <4>;
- reg = < 0x10A00000 0x10000 >;
+ reg = < 0x10a00000 0x10000 >;
clocks = <&ext>;
xlnx,clk-freq = <0x5f5e100>;
xlnx,family = "Artix7";
@@ -106,9 +106,9 @@
#address-cells = <1>;
#size-cells = <0>;
- ad7420@4B {
+ ad7420@4b {
compatible = "adi,adt7420";
- reg = <0x4B>;
+ reg = <0x4b>;
};
} ;
};
diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 43fcd35e2957..94096299fc56 100644
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -58,6 +58,7 @@ static __inline__ void atomic_##op(int i, atomic_t * v) \
if (kernel_uses_llsc) { \
int temp; \
\
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set "MIPS_ISA_LEVEL" \n" \
@@ -85,6 +86,7 @@ static __inline__ int atomic_##op##_return_relaxed(int i, atomic_t * v) \
if (kernel_uses_llsc) { \
int temp; \
\
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set "MIPS_ISA_LEVEL" \n" \
@@ -118,6 +120,7 @@ static __inline__ int atomic_fetch_##op##_relaxed(int i, atomic_t * v) \
if (kernel_uses_llsc) { \
int temp; \
\
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set "MIPS_ISA_LEVEL" \n" \
@@ -256,6 +259,7 @@ static __inline__ void atomic64_##op(long i, atomic64_t * v) \
if (kernel_uses_llsc) { \
long temp; \
\
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set "MIPS_ISA_LEVEL" \n" \
@@ -283,6 +287,7 @@ static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v) \
if (kernel_uses_llsc) { \
long temp; \
\
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set "MIPS_ISA_LEVEL" \n" \
@@ -316,6 +321,7 @@ static __inline__ long atomic64_fetch_##op##_relaxed(long i, atomic64_t * v) \
if (kernel_uses_llsc) { \
long temp; \
\
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set "MIPS_ISA_LEVEL" \n" \
diff --git a/arch/mips/include/asm/barrier.h b/arch/mips/include/asm/barrier.h
index a5eb1bb199a7..b7f6ac5e513c 100644
--- a/arch/mips/include/asm/barrier.h
+++ b/arch/mips/include/asm/barrier.h
@@ -222,6 +222,42 @@
#define __smp_mb__before_atomic() __smp_mb__before_llsc()
#define __smp_mb__after_atomic() smp_llsc_mb()
+/*
+ * Some Loongson 3 CPUs have a bug wherein execution of a memory access (load,
+ * store or pref) in between an ll & sc can cause the sc instruction to
+ * erroneously succeed, breaking atomicity. Whilst it's unusual to write code
+ * containing such sequences, this bug bites harder than we might otherwise
+ * expect due to reordering & speculation:
+ *
+ * 1) A memory access appearing prior to the ll in program order may actually
+ * be executed after the ll - this is the reordering case.
+ *
+ * In order to avoid this we need to place a memory barrier (ie. a sync
+ * instruction) prior to every ll instruction, in between it & any earlier
+ * memory access instructions. Many of these cases are already covered by
+ * smp_mb__before_llsc() but for the remaining cases, typically ones in
+ * which multiple CPUs may operate on a memory location but ordering is not
+ * usually guaranteed, we use loongson_llsc_mb() below.
+ *
+ * This reordering case is fixed by 3A R2 CPUs, ie. 3A2000 models and later.
+ *
+ * 2) If a conditional branch exists between an ll & sc with a target outside
+ * of the ll-sc loop, for example an exit upon value mismatch in cmpxchg()
+ * or similar, then misprediction of the branch may allow speculative
+ * execution of memory accesses from outside of the ll-sc loop.
+ *
+ * In order to avoid this we need a memory barrier (ie. a sync instruction)
+ * at each affected branch target, for which we also use loongson_llsc_mb()
+ * defined below.
+ *
+ * This case affects all current Loongson 3 CPUs.
+ */
+#ifdef CONFIG_CPU_LOONGSON3_WORKAROUNDS /* Loongson-3's LLSC workaround */
+#define loongson_llsc_mb() __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory")
+#else
+#define loongson_llsc_mb() do { } while (0)
+#endif
+
#include <asm-generic/barrier.h>
#endif /* __ASM_BARRIER_H */
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
index c4675957b21b..830c93a010c3 100644
--- a/arch/mips/include/asm/bitops.h
+++ b/arch/mips/include/asm/bitops.h
@@ -69,6 +69,7 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
: "ir" (1UL << bit), GCC_OFF_SMALL_ASM() (*m));
#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
+ loongson_llsc_mb();
do {
__asm__ __volatile__(
" " __LL "%0, %1 # set_bit \n"
@@ -79,6 +80,7 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
} while (unlikely(!temp));
#endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
} else if (kernel_uses_llsc) {
+ loongson_llsc_mb();
do {
__asm__ __volatile__(
" .set push \n"
@@ -123,6 +125,7 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
: "ir" (~(1UL << bit)));
#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
+ loongson_llsc_mb();
do {
__asm__ __volatile__(
" " __LL "%0, %1 # clear_bit \n"
@@ -133,6 +136,7 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
} while (unlikely(!temp));
#endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
} else if (kernel_uses_llsc) {
+ loongson_llsc_mb();
do {
__asm__ __volatile__(
" .set push \n"
@@ -193,6 +197,7 @@ static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
+ loongson_llsc_mb();
do {
__asm__ __volatile__(
" .set push \n"
diff --git a/arch/mips/include/asm/futex.h b/arch/mips/include/asm/futex.h
index c14d798f3888..b83b0397462d 100644
--- a/arch/mips/include/asm/futex.h
+++ b/arch/mips/include/asm/futex.h
@@ -50,6 +50,7 @@
"i" (-EFAULT) \
: "memory"); \
} else if (cpu_has_llsc) { \
+ loongson_llsc_mb(); \
__asm__ __volatile__( \
" .set push \n" \
" .set noat \n" \
@@ -163,6 +164,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
"i" (-EFAULT)
: "memory");
} else if (cpu_has_llsc) {
+ loongson_llsc_mb();
__asm__ __volatile__(
"# futex_atomic_cmpxchg_inatomic \n"
" .set push \n"
@@ -192,6 +194,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
: GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
"i" (-EFAULT)
: "memory");
+ loongson_llsc_mb();
} else
return -ENOSYS;
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 57933fc8fd98..910851c62db3 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -228,6 +228,7 @@ static inline void set_pte(pte_t *ptep, pte_t pteval)
: [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
: [global] "r" (page_global));
} else if (kernel_uses_llsc) {
+ loongson_llsc_mb();
__asm__ __volatile__ (
" .set push \n"
" .set "MIPS_ISA_ARCH_LEVEL" \n"
@@ -242,6 +243,7 @@ static inline void set_pte(pte_t *ptep, pte_t pteval)
" .set pop \n"
: [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
: [global] "r" (page_global));
+ loongson_llsc_mb();
}
#else /* !CONFIG_SMP */
if (pte_none(*buddy))
diff --git a/arch/mips/kernel/mips-cm.c b/arch/mips/kernel/mips-cm.c
index 8f5bd04f320a..7f3f136572de 100644
--- a/arch/mips/kernel/mips-cm.c
+++ b/arch/mips/kernel/mips-cm.c
@@ -457,5 +457,5 @@ void mips_cm_error_report(void)
}
/* reprime cause register */
- write_gcr_error_cause(0);
+ write_gcr_error_cause(cm_error);
}
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 6829a064aac8..339870ed92f7 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -371,7 +371,7 @@ static inline int is_sp_move_ins(union mips_instruction *ip, int *frame_size)
static int get_frame_info(struct mips_frame_info *info)
{
bool is_mmips = IS_ENABLED(CONFIG_CPU_MICROMIPS);
- union mips_instruction insn, *ip, *ip_end;
+ union mips_instruction insn, *ip;
const unsigned int max_insns = 128;
unsigned int last_insn_size = 0;
unsigned int i;
@@ -384,10 +384,9 @@ static int get_frame_info(struct mips_frame_info *info)
if (!ip)
goto err;
- ip_end = (void *)ip + info->func_size;
-
- for (i = 0; i < max_insns && ip < ip_end; i++) {
+ for (i = 0; i < max_insns; i++) {
ip = (void *)ip + last_insn_size;
+
if (is_mmips && mm_insn_16bit(ip->halfword[0])) {
insn.word = ip->halfword[0] << 16;
last_insn_size = 2;
diff --git a/arch/mips/loongson64/Platform b/arch/mips/loongson64/Platform
index 0fce4608aa88..c1a4d4dc4665 100644
--- a/arch/mips/loongson64/Platform
+++ b/arch/mips/loongson64/Platform
@@ -23,6 +23,29 @@ ifdef CONFIG_CPU_LOONGSON2F_WORKAROUNDS
endif
cflags-$(CONFIG_CPU_LOONGSON3) += -Wa,--trap
+
+#
+# Some versions of binutils, not currently mainline as of 2019/02/04, support
+# an -mfix-loongson3-llsc flag which emits a sync prior to each ll instruction
+# to work around a CPU bug (see loongson_llsc_mb() in asm/barrier.h for a
+# description).
+#
+# We disable this in order to prevent the assembler meddling with the
+# instruction that labels refer to, ie. if we label an ll instruction:
+#
+# 1: ll v0, 0(a0)
+#
+# ...then with the assembler fix applied the label may actually point at a sync
+# instruction inserted by the assembler, and if we were using the label in an
+# exception table the table would no longer contain the address of the ll
+# instruction.
+#
+# Avoid this by explicitly disabling that assembler behaviour. If upstream
+# binutils does not merge support for the flag then we can revisit & remove
+# this later - for now it ensures vendor toolchains don't cause problems.
+#
+cflags-$(CONFIG_CPU_LOONGSON3) += $(call as-option,-Wa$(comma)-mno-fix-loongson3-llsc,)
+
#
# binutils from v2.25 on and gcc starting from v4.9.0 treat -march=loongson3a
# as MIPS64 R2; older versions as just R1. This leaves the possibility open
diff --git a/arch/mips/loongson64/common/reset.c b/arch/mips/loongson64/common/reset.c
index a60715e11306..b26892ce871c 100644
--- a/arch/mips/loongson64/common/reset.c
+++ b/arch/mips/loongson64/common/reset.c
@@ -59,7 +59,12 @@ static void loongson_poweroff(void)
{
#ifndef CONFIG_LEFI_FIRMWARE_INTERFACE
mach_prepare_shutdown();
- unreachable();
+
+ /*
+ * It needs a wait loop here, but mips/kernel/reset.c already calls
+ * a generic delay loop, machine_hang(), so simply return.
+ */
+ return;
#else
void (*fw_poweroff)(void) = (void *)loongson_sysconf.poweroff_addr;
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 37b1cb246332..65b6e85447b1 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -932,6 +932,8 @@ build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
* to mimic that here by taking a load/istream page
* fault.
*/
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(p, 0);
UASM_i_LA(p, ptr, (unsigned long)tlb_do_page_fault_0);
uasm_i_jr(p, ptr);
@@ -1646,6 +1648,8 @@ static void
iPTE_LW(u32 **p, unsigned int pte, unsigned int ptr)
{
#ifdef CONFIG_SMP
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(p, 0);
# ifdef CONFIG_PHYS_ADDR_T_64BIT
if (cpu_has_64bits)
uasm_i_lld(p, pte, 0, ptr);
@@ -2259,6 +2263,8 @@ static void build_r4000_tlb_load_handler(void)
#endif
uasm_l_nopage_tlbl(&l, p);
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(&p, 0);
build_restore_work_registers(&p);
#ifdef CONFIG_CPU_MICROMIPS
if ((unsigned long)tlb_do_page_fault_0 & 1) {
@@ -2313,6 +2319,8 @@ static void build_r4000_tlb_store_handler(void)
#endif
uasm_l_nopage_tlbs(&l, p);
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(&p, 0);
build_restore_work_registers(&p);
#ifdef CONFIG_CPU_MICROMIPS
if ((unsigned long)tlb_do_page_fault_1 & 1) {
@@ -2368,6 +2376,8 @@ static void build_r4000_tlb_modify_handler(void)
#endif
uasm_l_nopage_tlbm(&l, p);
+ if (IS_ENABLED(CONFIG_CPU_LOONGSON3_WORKAROUNDS))
+ uasm_i_sync(&p, 0);
build_restore_work_registers(&p);
#ifdef CONFIG_CPU_MICROMIPS
if ((unsigned long)tlb_do_page_fault_1 & 1) {
diff --git a/arch/mips/pci/pci-octeon.c b/arch/mips/pci/pci-octeon.c
index 5017d5843c5a..fc29b85cfa92 100644
--- a/arch/mips/pci/pci-octeon.c
+++ b/arch/mips/pci/pci-octeon.c
@@ -568,6 +568,11 @@ static int __init octeon_pci_setup(void)
if (octeon_has_feature(OCTEON_FEATURE_PCIE))
return 0;
+ if (!octeon_is_pci_host()) {
+ pr_notice("Not in host mode, PCI Controller not initialized\n");
+ return 0;
+ }
+
/* Point pcibios_map_irq() to the PCI version of it */
octeon_pcibios_map_irq = octeon_pci_pcibios_map_irq;
@@ -579,11 +584,6 @@ static int __init octeon_pci_setup(void)
else
octeon_dma_bar_type = OCTEON_DMA_BAR_TYPE_BIG;
- if (!octeon_is_pci_host()) {
- pr_notice("Not in host mode, PCI Controller not initialized\n");
- return 0;
- }
-
/* PCI I/O and PCI MEM values */
set_io_port_base(OCTEON_PCI_IOSPACE_BASE);
ioport_resource.start = 0;
diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile
index f6fd340e39c2..0ede4deb8181 100644
--- a/arch/mips/vdso/Makefile
+++ b/arch/mips/vdso/Makefile
@@ -8,6 +8,7 @@ ccflags-vdso := \
$(filter -E%,$(KBUILD_CFLAGS)) \
$(filter -mmicromips,$(KBUILD_CFLAGS)) \
$(filter -march=%,$(KBUILD_CFLAGS)) \
+ $(filter -m%-float,$(KBUILD_CFLAGS)) \
-D__VDSO__
ifdef CONFIG_CC_IS_CLANG
@@ -129,7 +130,7 @@ $(obj)/%-o32.o: $(src)/%.c FORCE
$(call cmd,force_checksrc)
$(call if_changed_rule,cc_o_c)
-$(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := -mabi=32
+$(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=32
$(obj)/vdso-o32.lds: $(src)/vdso.lds.S FORCE
$(call if_changed_dep,cpp_lds_S)
@@ -169,7 +170,7 @@ $(obj)/%-n32.o: $(src)/%.c FORCE
$(call cmd,force_checksrc)
$(call if_changed_rule,cc_o_c)
-$(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := -mabi=n32
+$(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=n32
$(obj)/vdso-n32.lds: $(src)/vdso.lds.S FORCE
$(call if_changed_dep,cpp_lds_S)