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-rw-r--r--arch/mips/include/asm/bmips.h10
-rw-r--r--arch/mips/include/asm/compiler.h35
-rw-r--r--arch/mips/include/asm/io.h14
-rw-r--r--arch/mips/include/asm/kexec.h6
-rw-r--r--arch/mips/include/asm/mach-ath79/ar933x_uart.h4
-rw-r--r--arch/mips/include/asm/netlogic/xlr/fmn.h2
-rw-r--r--arch/mips/include/asm/octeon/cvmx-pko.h2
-rw-r--r--arch/mips/include/asm/smp.h12
-rw-r--r--arch/mips/include/asm/thread_info.h20
9 files changed, 78 insertions, 27 deletions
diff --git a/arch/mips/include/asm/bmips.h b/arch/mips/include/asm/bmips.h
index a92aee7b977a..23f55af7d6ba 100644
--- a/arch/mips/include/asm/bmips.h
+++ b/arch/mips/include/asm/bmips.h
@@ -75,11 +75,11 @@ static inline int register_bmips_smp_ops(void)
#endif
}
-extern char bmips_reset_nmi_vec;
-extern char bmips_reset_nmi_vec_end;
-extern char bmips_smp_movevec;
-extern char bmips_smp_int_vec;
-extern char bmips_smp_int_vec_end;
+extern char bmips_reset_nmi_vec[];
+extern char bmips_reset_nmi_vec_end[];
+extern char bmips_smp_movevec[];
+extern char bmips_smp_int_vec[];
+extern char bmips_smp_int_vec_end[];
extern int bmips_smp_enabled;
extern int bmips_cpu_offset;
diff --git a/arch/mips/include/asm/compiler.h b/arch/mips/include/asm/compiler.h
index e081a265f422..cc2eb1b06050 100644
--- a/arch/mips/include/asm/compiler.h
+++ b/arch/mips/include/asm/compiler.h
@@ -8,6 +8,41 @@
#ifndef _ASM_COMPILER_H
#define _ASM_COMPILER_H
+/*
+ * With GCC 4.5 onwards we can use __builtin_unreachable to indicate to the
+ * compiler that a particular code path will never be hit. This allows it to be
+ * optimised out of the generated binary.
+ *
+ * Unfortunately at least GCC 4.6.3 through 7.3.0 inclusive suffer from a bug
+ * that can lead to instructions from beyond an unreachable statement being
+ * incorrectly reordered into earlier delay slots if the unreachable statement
+ * is the only content of a case in a switch statement. This can lead to
+ * seemingly random behaviour, such as invalid memory accesses from incorrectly
+ * reordered loads or stores. See this potential GCC fix for details:
+ *
+ * https://gcc.gnu.org/ml/gcc-patches/2015-09/msg00360.html
+ *
+ * It is unclear whether GCC 8 onwards suffer from the same issue - nothing
+ * relevant is mentioned in GCC 8 release notes and nothing obviously relevant
+ * stands out in GCC commit logs, but these newer GCC versions generate very
+ * different code for the testcase which doesn't exhibit the bug.
+ *
+ * GCC also handles stack allocation suboptimally when calling noreturn
+ * functions or calling __builtin_unreachable():
+ *
+ * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
+ *
+ * We work around both of these issues by placing a volatile asm statement,
+ * which GCC is prevented from reordering past, prior to __builtin_unreachable
+ * calls.
+ *
+ * The .insn statement is required to ensure that any branches to the
+ * statement, which sadly must be kept due to the asm statement, are known to
+ * be branches to code and satisfy linker requirements for microMIPS kernels.
+ */
+#undef barrier_before_unreachable
+#define barrier_before_unreachable() asm volatile(".insn")
+
#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
#define GCC_IMM_ASM() "n"
#define GCC_REG_ACCUM "$0"
diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
index 06049b6b3ddd..5dfae80264b9 100644
--- a/arch/mips/include/asm/io.h
+++ b/arch/mips/include/asm/io.h
@@ -60,21 +60,11 @@
* instruction, so the lower 16 bits must be zero. Should be true on
* on any sane architecture; generic code does not use this assumption.
*/
-extern const unsigned long mips_io_port_base;
+extern unsigned long mips_io_port_base;
-/*
- * Gcc will generate code to load the value of mips_io_port_base after each
- * function call which may be fairly wasteful in some cases. So we don't
- * play quite by the book. We tell gcc mips_io_port_base is a long variable
- * which solves the code generation issue. Now we need to violate the
- * aliasing rules a little to make initialization possible and finally we
- * will need the barrier() to fight side effects of the aliasing chat.
- * This trickery will eventually collapse under gcc's optimizer. Oh well.
- */
static inline void set_io_port_base(unsigned long base)
{
- * (unsigned long *) &mips_io_port_base = base;
- barrier();
+ mips_io_port_base = base;
}
/*
diff --git a/arch/mips/include/asm/kexec.h b/arch/mips/include/asm/kexec.h
index 493a3cc7c39a..cfdbe66575f4 100644
--- a/arch/mips/include/asm/kexec.h
+++ b/arch/mips/include/asm/kexec.h
@@ -12,11 +12,11 @@
#include <asm/stacktrace.h>
/* Maximum physical address we can use pages from */
-#define KEXEC_SOURCE_MEMORY_LIMIT (0x20000000)
+#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
/* Maximum address we can reach in physical address mode */
-#define KEXEC_DESTINATION_MEMORY_LIMIT (0x20000000)
+#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
/* Maximum address we can use for the control code buffer */
-#define KEXEC_CONTROL_MEMORY_LIMIT (0x20000000)
+#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL)
/* Reserve 3*4096 bytes for board-specific info */
#define KEXEC_CONTROL_PAGE_SIZE (4096 + 3*4096)
diff --git a/arch/mips/include/asm/mach-ath79/ar933x_uart.h b/arch/mips/include/asm/mach-ath79/ar933x_uart.h
index c2917b39966b..bba2c8837951 100644
--- a/arch/mips/include/asm/mach-ath79/ar933x_uart.h
+++ b/arch/mips/include/asm/mach-ath79/ar933x_uart.h
@@ -27,8 +27,8 @@
#define AR933X_UART_CS_PARITY_S 0
#define AR933X_UART_CS_PARITY_M 0x3
#define AR933X_UART_CS_PARITY_NONE 0
-#define AR933X_UART_CS_PARITY_ODD 1
-#define AR933X_UART_CS_PARITY_EVEN 2
+#define AR933X_UART_CS_PARITY_ODD 2
+#define AR933X_UART_CS_PARITY_EVEN 3
#define AR933X_UART_CS_IF_MODE_S 2
#define AR933X_UART_CS_IF_MODE_M 0x3
#define AR933X_UART_CS_IF_MODE_NONE 0
diff --git a/arch/mips/include/asm/netlogic/xlr/fmn.h b/arch/mips/include/asm/netlogic/xlr/fmn.h
index 5604db3d1836..d79c68fa78d9 100644
--- a/arch/mips/include/asm/netlogic/xlr/fmn.h
+++ b/arch/mips/include/asm/netlogic/xlr/fmn.h
@@ -301,8 +301,6 @@ static inline int nlm_fmn_send(unsigned int size, unsigned int code,
for (i = 0; i < 8; i++) {
nlm_msgsnd(dest);
status = nlm_read_c2_status0();
- if ((status & 0x2) == 1)
- pr_info("Send pending fail!\n");
if ((status & 0x4) == 0)
return 0;
}
diff --git a/arch/mips/include/asm/octeon/cvmx-pko.h b/arch/mips/include/asm/octeon/cvmx-pko.h
index 5f47f76ed510..20eb9c46a75a 100644
--- a/arch/mips/include/asm/octeon/cvmx-pko.h
+++ b/arch/mips/include/asm/octeon/cvmx-pko.h
@@ -611,7 +611,7 @@ static inline void cvmx_pko_get_port_status(uint64_t port_num, uint64_t clear,
pko_reg_read_idx.s.index = cvmx_pko_get_base_queue(port_num);
cvmx_write_csr(CVMX_PKO_REG_READ_IDX, pko_reg_read_idx.u64);
debug8.u64 = cvmx_read_csr(CVMX_PKO_MEM_DEBUG8);
- status->doorbell = debug8.cn58xx.doorbell;
+ status->doorbell = debug8.cn50xx.doorbell;
}
}
diff --git a/arch/mips/include/asm/smp.h b/arch/mips/include/asm/smp.h
index 060f23ff1817..258158c34df1 100644
--- a/arch/mips/include/asm/smp.h
+++ b/arch/mips/include/asm/smp.h
@@ -25,7 +25,17 @@ extern cpumask_t cpu_sibling_map[];
extern cpumask_t cpu_core_map[];
extern cpumask_t cpu_foreign_map[];
-#define raw_smp_processor_id() (current_thread_info()->cpu)
+static inline int raw_smp_processor_id(void)
+{
+#if defined(__VDSO__)
+ extern int vdso_smp_processor_id(void)
+ __compiletime_error("VDSO should not call smp_processor_id()");
+ return vdso_smp_processor_id();
+#else
+ return current_thread_info()->cpu;
+#endif
+}
+#define raw_smp_processor_id raw_smp_processor_id
/* Map from cpu id to sequential logical cpu number. This will only
not be idempotent when cpus failed to come on-line. */
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index e309d8fcb516..da1cb0499d6c 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -52,8 +52,26 @@ struct thread_info {
#define init_thread_info (init_thread_union.thread_info)
#define init_stack (init_thread_union.stack)
-/* How to get the thread information struct from C. */
+/*
+ * A pointer to the struct thread_info for the currently executing thread is
+ * held in register $28/$gp.
+ *
+ * We declare __current_thread_info as a global register variable rather than a
+ * local register variable within current_thread_info() because clang doesn't
+ * support explicit local register variables.
+ *
+ * When building the VDSO we take care not to declare the global register
+ * variable because this causes GCC to not preserve the value of $28/$gp in
+ * functions that change its value (which is common in the PIC VDSO when
+ * accessing the GOT). Since the VDSO shouldn't be accessing
+ * __current_thread_info anyway we declare it extern in order to cause a link
+ * failure if it's referenced.
+ */
+#ifdef __VDSO__
+extern struct thread_info *__current_thread_info;
+#else
register struct thread_info *__current_thread_info __asm__("$28");
+#endif
static inline struct thread_info *current_thread_info(void)
{