On Thu, Oct 29, 2020 at 2:40 AM Greg Kroah-Hartman <gre...@linuxfoundation.org> wrote: > > On Wed, Oct 28, 2020 at 06:43:59PM -0300, Daniel Gutson wrote: > > This patch separates the writing part of the intel-spi drivers > > so the 'dangerous' part can be set/unset independently. > > This way, the kernel can be configured to include the reading > > parts of the driver which can be used without > > the dangerous write operations that can turn the system > > unbootable. > > > > Signed-off-by: Daniel Gutson <daniel.gut...@eclypsium.com> > > --- > > drivers/mtd/spi-nor/controllers/Kconfig | 39 ++++++++++++--------- > > drivers/mtd/spi-nor/controllers/intel-spi.c | 12 +++++-- > > 2 files changed, 33 insertions(+), 18 deletions(-) > > > > diff --git a/drivers/mtd/spi-nor/controllers/Kconfig > > b/drivers/mtd/spi-nor/controllers/Kconfig > > index 5c0e0ec2e6d1..491c755fea49 100644 > > --- a/drivers/mtd/spi-nor/controllers/Kconfig > > +++ b/drivers/mtd/spi-nor/controllers/Kconfig > > @@ -31,34 +31,41 @@ config SPI_INTEL_SPI > > tristate > > > > config SPI_INTEL_SPI_PCI > > - tristate "Intel PCH/PCU SPI flash PCI driver (DANGEROUS)" > > + tristate "Intel PCH/PCU SPI flash PCI driver" > > depends on X86 && PCI > > select SPI_INTEL_SPI > > help > > - This enables PCI support for the Intel PCH/PCU SPI controller in > > - master mode. This controller is present in modern Intel hardware > > - and is used to hold BIOS and other persistent settings. Using > > - this driver it is possible to upgrade BIOS directly from Linux. > > - > > - Say N here unless you know what you are doing. Overwriting the > > - SPI flash may render the system unbootable. > > + This enables read only PCI support for the Intel PCH/PCU SPI > > + controller in master mode. This controller is present in modern > > + Intel hardware and is used to hold BIOS and other persistent > > settings. > > + Using this driver it is possible to read the SPI chip directly > > + from Linux. > > > > To compile this driver as a module, choose M here: the module > > will be called intel-spi-pci. > > > > config SPI_INTEL_SPI_PLATFORM > > - tristate "Intel PCH/PCU SPI flash platform driver (DANGEROUS)" > > + tristate "Intel PCH/PCU SPI flash platform driver" > > depends on X86 > > select SPI_INTEL_SPI > > help > > - This enables platform support for the Intel PCH/PCU SPI > > + This enables read only platform support for the Intel PCH/PCU SPI > > controller in master mode. This controller is present in modern > > - Intel hardware and is used to hold BIOS and other persistent > > - settings. Using this driver it is possible to upgrade BIOS > > - directly from Linux. > > + Intel hardware and is used to hold BIOS and other persistent > > settings. > > + Using this driver it is possible to read the SPI chip directly > > + from Linux. > > + > > + To compile this driver as a module, choose M here: the module > > + will be called intel-spi-pci. > > + > > +config SPI_INTEL_SPI_WRITE > > + bool "Intel PCH/PCU SPI flash drivers write operations (DANGEROUS)" > > + depends on SPI_INTEL_SPI_PCI || SPI_INTEL_SPI_PLATFORM > > + help > > + This enables full read/write support for the Intel PCH/PCU SPI > > + controller. > > + Using this option it may be possible to upgrade BIOS directly > > + from Linux. > > > > Say N here unless you know what you are doing. Overwriting the > > SPI flash may render the system unbootable. > > - > > - To compile this driver as a module, choose M here: the module > > - will be called intel-spi-platform. > > diff --git a/drivers/mtd/spi-nor/controllers/intel-spi.c > > b/drivers/mtd/spi-nor/controllers/intel-spi.c > > index b54a56a68100..8d8053395c3d 100644 > > --- a/drivers/mtd/spi-nor/controllers/intel-spi.c > > +++ b/drivers/mtd/spi-nor/controllers/intel-spi.c > > @@ -266,6 +266,7 @@ static int intel_spi_read_block(struct intel_spi *ispi, > > void *buf, size_t size) > > return 0; > > } > > > > +#ifdef CONFIG_SPI_INTEL_SPI_WRITE > > <snip> > > Please do not add #ifdef to .c files, that's not the proper kernel > coding style at all, and just makes maintaining this file much much > harder over time. > > Split things out into two different files if you really need to do this.
What about the static functions that I'll need to turn non-static and in a header file? I mean, the functions that the functions in the new file will have to call. Should I do that, turn static functions into non-static and declared in a header file? > > thanks, > > greg k-h -- Daniel Gutson Engineering Director Eclypsium, Inc. Below The Surface: Get the latest threat research and insights on firmware and supply chain threats from the research team at Eclypsium. https://eclypsium.com/research/#threatreport
