Merge tag 'xtensa-20220325' of https://github.com/jcmvbkbc/linux-xtensa

Pull Xtensa updates from Max Filippov:

 - remove dependency on the compiler's libgcc

 - allow selection of internal kernel ABI via Kconfig

 - enable compiler plugins support for gcc-12 or newer

 - various minor cleanups and fixes

* tag 'xtensa-20220325' of https://github.com/jcmvbkbc/linux-xtensa:
  xtensa: define update_mmu_tlb function
  xtensa: fix xtensa_wsr always writing 0
  xtensa: enable plugin support
  xtensa: clean up kernel exit assembly code
  xtensa: rearrange NMI exit path
  xtensa: merge stack alignment definitions
  xtensa: fix DTC warning unit_address_format
  xtensa: fix stop_machine_cpuslocked call in patch_text
  xtensa: make secondary reset vector support conditional
  xtensa: add kernel ABI selection to Kconfig
  xtensa: don't link with libgcc
  xtensa: add helpers for division, remainder and shifts
  xtensa: add missing XCHAL_HAVE_WINDOWED check
  xtensa: use XCHAL_NUM_AREGS as pt_regs::areg size
  xtensa: rename PT_SIZE to PT_KERNEL_SIZE
  xtensa: Remove unused early_read_config_byte() et al declarations
  xtensa: use strscpy to copy strings
  net: xtensa: use strscpy to copy strings

Author: torvalds

arch/xtensa/Kconfig

@@ -21,6 +21,9 @@ config XTENSA
 	select DMA_REMAP if MMU
 	select GENERIC_ATOMIC64
 	select GENERIC_IRQ_SHOW
+	select GENERIC_LIB_CMPDI2
+	select GENERIC_LIB_MULDI3
+	select GENERIC_LIB_UCMPDI2
 	select GENERIC_PCI_IOMAP
 	select GENERIC_SCHED_CLOCK
 	select HAVE_ARCH_AUDITSYSCALL
@@ -32,6 +35,7 @@ config XTENSA
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_EXIT_THREAD
 	select HAVE_FUNCTION_TRACER
+	select HAVE_GCC_PLUGINS if GCC_VERSION >= 120000
 	select HAVE_HW_BREAKPOINT if PERF_EVENTS
 	select HAVE_IRQ_TIME_ACCOUNTING
 	select HAVE_PCI
@@ -89,6 +93,9 @@ config CPU_BIG_ENDIAN
 config CPU_LITTLE_ENDIAN
 	def_bool !CPU_BIG_ENDIAN
 
+config CC_HAVE_CALL0_ABI
+	def_bool $(success,test "$(shell,echo __XTENSA_CALL0_ABI__ | $(CC) -mabi=call0 -E -P - 2>/dev/null)" = 1)
+
 menu "Processor type and features"
 
 choice
@@ -221,6 +228,15 @@ config HOTPLUG_CPU
 
 	  Say N if you want to disable CPU hotplug.
 
+config SECONDARY_RESET_VECTOR
+	bool "Secondary cores use alternative reset vector"
+	default y
+	depends on HAVE_SMP
+	help
+	  Secondary cores may be configured to use alternative reset vector,
+	  or all cores may use primary reset vector.
+	  Say Y here to supply handler for the alternative reset location.
+
 config FAST_SYSCALL_XTENSA
 	bool "Enable fast atomic syscalls"
 	default n
@@ -247,6 +263,38 @@ config FAST_SYSCALL_SPILL_REGISTERS
 
 	  If unsure, say N.
 
+choice
+	prompt "Kernel ABI"
+	default KERNEL_ABI_DEFAULT
+	help
+	  Select ABI for the kernel code. This ABI is independent of the
+	  supported userspace ABI and any combination of the
+	  kernel/userspace ABI is possible and should work.
+
+	  In case both kernel and userspace support only call0 ABI
+	  all register windows support code will be omitted from the
+	  build.
+
+	  If unsure, choose the default ABI.
+
+config KERNEL_ABI_DEFAULT
+	bool "Default ABI"
+	help
+	  Select this option to compile kernel code with the default ABI
+	  selected for the toolchain.
+	  Normally cores with windowed registers option use windowed ABI and
+	  cores without it use call0 ABI.
+
+config KERNEL_ABI_CALL0
+	bool "Call0 ABI" if CC_HAVE_CALL0_ABI
+	help
+	  Select this option to compile kernel code with call0 ABI even with
+	  toolchain that defaults to windowed ABI.
+	  When this option is not selected the default toolchain ABI will
+	  be used for the kernel code.
+
+endchoice
+
 config USER_ABI_CALL0
 	bool
 

arch/xtensa/Makefile

@@ -35,6 +35,10 @@ KBUILD_CFLAGS += -ffreestanding -D__linux__
 KBUILD_CFLAGS += -pipe -mlongcalls -mtext-section-literals
 KBUILD_CFLAGS += $(call cc-option,-mforce-no-pic,)
 KBUILD_CFLAGS += $(call cc-option,-mno-serialize-volatile,)
+ifneq ($(CONFIG_KERNEL_ABI_CALL0),)
+KBUILD_CFLAGS += -mabi=call0
+KBUILD_AFLAGS += -mabi=call0
+endif
 
 KBUILD_AFLAGS += -mlongcalls -mtext-section-literals
 
@@ -51,13 +55,9 @@ KBUILD_CPPFLAGS += $(patsubst %,-I$(srctree)/%include,$(vardirs) $(plfdirs))
 
 KBUILD_DEFCONFIG := iss_defconfig
 
-# Find libgcc.a
-
-LIBGCC := $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name)
-
 head-y		:= arch/xtensa/kernel/head.o
 
-libs-y		+= arch/xtensa/lib/ $(LIBGCC)
+libs-y		+= arch/xtensa/lib/
 
 boot		:= arch/xtensa/boot
 

arch/xtensa/boot/dts/xtfpga-flash-128m.dtsi

@@ -8,19 +8,19 @@
 			reg = <0x00000000 0x08000000>;
 			bank-width = <2>;
 			device-width = <2>;
-			partition@0x0 {
+			partition@0 {
 				label = "data";
 				reg = <0x00000000 0x06000000>;
 			};
-			partition@0x6000000 {
+			partition@6000000 {
 				label = "boot loader area";
 				reg = <0x06000000 0x00800000>;
 			};
-			partition@0x6800000 {
+			partition@6800000 {
 				label = "kernel image";
 				reg = <0x06800000 0x017e0000>;
 			};
-			partition@0x7fe0000 {
+			partition@7fe0000 {
 				label = "boot environment";
 				reg = <0x07fe0000 0x00020000>;
 			};

arch/xtensa/boot/dts/xtfpga-flash-16m.dtsi

@@ -8,19 +8,19 @@
 			reg = <0x08000000 0x01000000>;
 			bank-width = <2>;
 			device-width = <2>;
-			partition@0x0 {
+			partition@0 {
 				label = "boot loader area";
 				reg = <0x00000000 0x00400000>;
 			};
-			partition@0x400000 {
+			partition@400000 {
 				label = "kernel image";
 				reg = <0x00400000 0x00600000>;
 			};
-			partition@0xa00000 {
+			partition@a00000 {
 				label = "data";
 				reg = <0x00a00000 0x005e0000>;
 			};
-			partition@0xfe0000 {
+			partition@fe0000 {
 				label = "boot environment";
 				reg = <0x00fe0000 0x00020000>;
 			};

arch/xtensa/boot/dts/xtfpga-flash-4m.dtsi

@@ -8,11 +8,11 @@
 			reg = <0x08000000 0x00400000>;
 			bank-width = <2>;
 			device-width = <2>;
-			partition@0x0 {
+			partition@0 {
 				label = "boot loader area";
 				reg = <0x00000000 0x003f0000>;
 			};
-			partition@0x3f0000 {
+			partition@3f0000 {
 				label = "boot environment";
 				reg = <0x003f0000 0x00010000>;
 			};

arch/xtensa/include/asm/asmmacro.h

@@ -191,7 +191,39 @@
 #endif
 	.endm
 
-#define XTENSA_STACK_ALIGNMENT		16
+	.macro	do_nsau cnt, val, tmp, a
+#if XCHAL_HAVE_NSA
+	nsau	\cnt, \val
+#else
+	mov	\a, \val
+	movi	\cnt, 0
+	extui	\tmp, \a, 16, 16
+	bnez	\tmp, 0f
+	movi	\cnt, 16
+	slli	\a, \a, 16
+0:
+	extui	\tmp, \a, 24, 8
+	bnez	\tmp, 1f
+	addi	\cnt, \cnt, 8
+	slli	\a, \a, 8
+1:
+	movi	\tmp, __nsau_data
+	extui	\a, \a, 24, 8
+	add	\tmp, \tmp, \a
+	l8ui	\tmp, \tmp, 0
+	add	\cnt, \cnt, \tmp
+#endif /* !XCHAL_HAVE_NSA */
+	.endm
+
+	.macro	do_abs dst, src, tmp
+#if XCHAL_HAVE_ABS
+	abs	\dst, \src
+#else
+	neg	\tmp, \src
+	movgez	\tmp, \src, \src
+	mov	\dst, \tmp
+#endif
+	.endm
 
 #if defined(__XTENSA_WINDOWED_ABI__)
 

arch/xtensa/include/asm/core.h

@@ -37,4 +37,11 @@
 #endif
 #endif
 
+/* Xtensa ABI requires stack alignment to be at least 16 */
+#if XCHAL_DATA_WIDTH > 16
+#define XTENSA_STACK_ALIGNMENT	XCHAL_DATA_WIDTH
+#else
+#define XTENSA_STACK_ALIGNMENT	16
+#endif
+
 #endif

arch/xtensa/include/asm/pci-bridge.h

@@ -73,13 +73,4 @@ static inline void pcibios_init_resource(struct resource *res,
 	res->child = NULL;
 }
 
-
-/* These are used for config access before all the PCI probing has been done. */
-int early_read_config_byte(struct pci_controller*, int, int, int, u8*);
-int early_read_config_word(struct pci_controller*, int, int, int, u16*);
-int early_read_config_dword(struct pci_controller*, int, int, int, u32*);
-int early_write_config_byte(struct pci_controller*, int, int, int, u8);
-int early_write_config_word(struct pci_controller*, int, int, int, u16);
-int early_write_config_dword(struct pci_controller*, int, int, int, u32);
-
 #endif	/* _XTENSA_PCI_BRIDGE_H */

arch/xtensa/include/asm/pgtable.h

@@ -412,6 +412,10 @@ extern  void update_mmu_cache(struct vm_area_struct * vma,
 
 typedef pte_t *pte_addr_t;
 
+void update_mmu_tlb(struct vm_area_struct *vma,
+		    unsigned long address, pte_t *ptep);
+#define __HAVE_ARCH_UPDATE_MMU_TLB
+
 #endif /* !defined (__ASSEMBLY__) */
 
 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG

arch/xtensa/include/asm/processor.h

@@ -18,11 +18,7 @@
 #include <asm/types.h>
 #include <asm/regs.h>
 
-/* Xtensa ABI requires stack alignment to be at least 16 */
-
-#define STACK_ALIGN (XCHAL_DATA_WIDTH > 16 ? XCHAL_DATA_WIDTH : 16)
-
-#define ARCH_SLAB_MINALIGN STACK_ALIGN
+#define ARCH_SLAB_MINALIGN XTENSA_STACK_ALIGNMENT
 
 /*
  * User space process size: 1 GB.
@@ -239,8 +235,8 @@ extern unsigned long __get_wchan(struct task_struct *p);
 
 #define xtensa_set_sr(x, sr) \
 	({ \
-	 unsigned int v = (unsigned int)(x); \
-	 __asm__ __volatile__ ("wsr %0, "__stringify(sr) :: "a"(v)); \
+	 __asm__ __volatile__ ("wsr %0, "__stringify(sr) :: \
+			       "a"((unsigned int)(x))); \
 	 })
 
 #define xtensa_get_sr(sr) \