# Use the default kernel version if the Makefile doesn't override it
LINUX_RELEASE?=1

ifdef CONFIG_TESTING_KERNEL
  KERNEL_PATCHVER:=$(KERNEL_TESTING_PATCHVER)
endif

LINUX_VERSION-4.9 = .257
LINUX_VERSION-4.14 = .221
LINUX_VERSION-4.19 = .175

LINUX_KERNEL_HASH-4.9.257 = 95e780fffc81de8217a31a3e6e212b69643f5344e9ba0dabaa6e426126f6d64f
LINUX_KERNEL_HASH-4.14.221 = ce2254075ff4846f13380c1cf4bec1e351e5996a7dd109c200e222e49fd2c7e9
LINUX_KERNEL_HASH-4.19.175 = ccee4b84ff2b16ad438e013bd211efea12f14e69f7cadb0e095fc89c781b2b25

remove_uri_prefix=$(subst git://,,$(subst http://,,$(subst https://,,$(1))))
sanitize_uri=$(call qstrip,$(subst @,_,$(subst :,_,$(subst .,_,$(subst -,_,$(subst /,_,$(1)))))))

ifneq ($(call qstrip,$(CONFIG_KERNEL_GIT_CLONE_URI)),)
  LINUX_VERSION:=$(call sanitize_uri,$(call remove_uri_prefix,$(CONFIG_KERNEL_GIT_CLONE_URI)))
  ifeq ($(call qstrip,$(CONFIG_KERNEL_GIT_REF)),)
    CONFIG_KERNEL_GIT_REF:=HEAD
  endif
  LINUX_VERSION:=$(LINUX_VERSION)-$(call sanitize_uri,$(CONFIG_KERNEL_GIT_REF))
else
ifdef KERNEL_PATCHVER
  LINUX_VERSION:=$(KERNEL_PATCHVER)$(strip $(LINUX_VERSION-$(KERNEL_PATCHVER)))
endif
ifdef KERNEL_TESTING_PATCHVER
  LINUX_TESTING_VERSION:=$(KERNEL_TESTING_PATCHVER)$(strip $(LINUX_VERSION-$(KERNEL_TESTING_PATCHVER)))
endif
endif

split_version=$(subst ., ,$(1))
merge_version=$(subst $(space),.,$(1))
KERNEL_BASE=$(firstword $(subst -, ,$(LINUX_VERSION)))
KERNEL=$(call merge_version,$(wordlist 1,2,$(call split_version,$(KERNEL_BASE))))
KERNEL_PATCHVER ?= $(KERNEL)

# disable the md5sum check for unknown kernel versions
LINUX_KERNEL_HASH:=$(LINUX_KERNEL_HASH-$(strip $(LINUX_VERSION)))
LINUX_KERNEL_HASH?=x