linux-toradex.git/arch/riscv/kernel/setup.c, branch v4.19 Linux kernel for Apalis and Colibri modules RISCV: Fix end PFN for low memory 2018-10-02T19:50:01+00:00 Atish Patra atish.patra@wdc.com 2018-09-11T18:30:18+00:00 ef1f2258748b675422ca0107e5bfb9ceeac675de Use memblock_end_of_DRAM which provides correct last low memory PFN. Without that, DMA32 region becomes empty resulting in zero pages being allocated for DMA32. This patch is based on earlier patch from palmer which never merged into 4.19. I just edited the commit text to make more sense. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
Use memblock_end_of_DRAM which provides correct last low memory
PFN. Without that, DMA32 region becomes empty resulting in zero
pages being allocated for DMA32.

This patch is based on earlier patch from palmer which never
merged into 4.19. I just edited the commit text to make more
sense.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
riscv: Do not overwrite initrd_start and initrd_end 2018-09-05T00:04:50+00:00 Guenter Roeck linux@roeck-us.net 2018-08-29T00:33:46+00:00 e866d3e84eb7c9588afb77604d417e8cc49fe216 setup_initrd() overwrites initrd_start and initrd_end if __initramfs_size is larger than 0, which is always true even if there is no embedded initramfs. This prevents booting qemu with "-initrd" parameter. Overwriting initrd_start and initrd_end is not necessary since __initramfs_start and __initramfs_size are used directly in populate_rootfs() to load the built-in initramfs, so just drop that code. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
setup_initrd() overwrites initrd_start and initrd_end if __initramfs_size
is larger than 0, which is always true even if there is no embedded
initramfs. This prevents booting qemu with "-initrd" parameter.
Overwriting initrd_start and initrd_end is not necessary since
__initramfs_start and __initramfs_size are used directly in
populate_rootfs() to load the built-in initramfs, so just drop
that code.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
RISC-V: Add early printk support via the SBI console 2018-08-13T15:31:30+00:00 Palmer Dabbelt palmer@sifive.com 2017-12-08T23:10:35+00:00 5b5c2a2c44d7225ab3abbcc7e1881b97ea9872dd This code lives entirely within the RISC-V arch code. I've left it within an "#ifdef CONFIG_EARLY_PRINTK" despite always having EARLY_PRINTK support on RISC-V just in case someone wants to remove it. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
This code lives entirely within the RISC-V arch code.  I've left it
within an "#ifdef CONFIG_EARLY_PRINTK" despite always having
EARLY_PRINTK support on RISC-V just in case someone wants to remove
it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
riscv: remove unnecessary of_platform_populate call 2018-07-04T21:12:38+00:00 Rob Herring robh@kernel.org 2018-06-19T21:41:34+00:00 f67f10b8a6c96ab6c1d6946d269e2ca5f9998cc2 The DT core will call of_platform_default_populate, so it is not necessary for arch specific code to call it unless there are custom match entries, auxdata or parent device. Neither of those apply here, so remove the call. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linux-riscv@lists.infradead.org Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
The DT core will call of_platform_default_populate, so it is not
necessary for arch specific code to call it unless there are custom
match entries, auxdata or parent device. Neither of those apply here, so
remove the call.

Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: linux-riscv@lists.infradead.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
riscv: add swiotlb support 2018-05-19T06:46:26+00:00 Christoph Hellwig hch@lst.de 2018-04-27T06:43:14+00:00 10314e09d044296bc50dec831aa85b3ae1acedf0 All RISC-V platforms today lack an IOMMU. However, legacy PCI devices sometimes require DMA-memory to be in the low 32 bits. To make this work, we enable the software-based bounce buffers from swiotlb. They only impose overhead when the device in question cannot address the full 64-bit address space, so a perfect fit. This patch assumes that DMA is coherent with the processor and the PCI bus. It also assumes that the processor and devices share a common address space. This is true for all RISC-V platforms so far. [changelog stolen from an earlier patch by Palmer Dabbelt that did the more complicated swiotlb wireup before the recent consolidation] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> 
All RISC-V platforms today lack an IOMMU. However, legacy PCI devices
sometimes require DMA-memory to be in the low 32 bits.  To make this work,
we enable the software-based bounce buffers from swiotlb.  They only impose
overhead when the device in question cannot address the full 64-bit address
space, so a perfect fit.

This patch assumes that DMA is coherent with the processor and the PCI
bus.  It also assumes that the processor and devices share a common
address space. This is true for all RISC-V platforms so far.

[changelog stolen from an earlier patch by Palmer Dabbelt that did the
 more complicated swiotlb wireup before the recent consolidation]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Rename sbi_save to parse_dtb to improve code readability 2018-02-20T18:56:26+00:00 Michael Clark michaeljclark@mac.com 2018-02-15T20:30:29+00:00 8b08f50152ff85a4780e5c385d2b65889406e842 The sbi_ prefix would seem to indicate an SBI interface, and save is not very specific. After applying this patch, reading head.S makes more sense. Signed-off-by: Michael Clark <michaeljclark@mac.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
The sbi_ prefix would seem to indicate an SBI interface, and save is not
very specific. After applying this patch, reading head.S makes more sense.

Signed-off-by: Michael Clark <michaeljclark@mac.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
riscv: add ZONE_DMA32 2018-01-31T03:14:27+00:00 Christoph Hellwig hch@lst.de 2018-01-16T08:37:50+00:00 5ec9c4ff0430e33b602cc0ff8ab9dec8ef548d28 This patch allows devices that require memory that can be addressed using 32-bit addresses to work easily on RISC-V systems. The newly improved dma-direct ops will tap into this pool automatically for 32-bit addressing. Based on an earlier patch from Wesley W. Terpstra. CC: Wesley W. Terpstra <terpstra@sifive.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
This patch allows devices that require memory that can be addressed
using 32-bit addresses to work easily on RISC-V systems.  The newly
improved dma-direct ops will tap into this pool automatically for
32-bit addressing.

Based on an earlier patch from Wesley W. Terpstra.

CC: Wesley W. Terpstra <terpstra@sifive.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
RISC-V: Remove mem_end command line processing 2018-01-31T03:09:53+00:00 Palmer Dabbelt palmer@sifive.com 2017-12-16T19:17:16+00:00 5d44bf2065e169dd857a4207505210fce25743e6 This is just some cruft left over from before the port converted to device tree. The right way to handle memory regions is to specify them in the device tree, which BBL (our simplest bootloader) is already capable of doing. This patch simply removes the cruft. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
This is just some cruft left over from before the port converted to
device tree.  The right way to handle memory regions is to specify them
in the device tree, which BBL (our simplest bootloader) is already
capable of doing.  This patch simply removes the cruft.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
RISC-V: Remove duplicate command-line parsing logic 2018-01-31T03:09:52+00:00 Michael Clark mjc@sifive.com 2017-12-16T19:17:02+00:00 3e076a7e049267e9c483674d0dd1caaca565dbef builtin_cmdline handling is present in drivers/of/fdt.c so the duplicate logic in arch/riscv/setup.c results in duplication of the builtin command line. e.g. CONFIG_CMDLINE="root=/dev/vda ro" gets appended twice and gives "root=/dev/vda ro root=/dev/vda ro" Before this patch: [ 0.000000] Kernel command line: root=/dev/vda ro root=/dev/vda ro After this patch: [ 0.000000] Kernel command line: root=/dev/vda ro Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
builtin_cmdline handling is present in drivers/of/fdt.c so the
duplicate logic in arch/riscv/setup.c results in duplication of
the builtin command line. e.g. CONFIG_CMDLINE="root=/dev/vda ro"
gets appended twice and gives "root=/dev/vda ro root=/dev/vda ro"

Before this patch:

[    0.000000] Kernel command line: root=/dev/vda ro root=/dev/vda ro

After this patch:

[    0.000000] Kernel command line: root=/dev/vda ro

Signed-off-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
RISC-V: Remove unused CONFIG_HVC_RISCV_SBI code 2017-12-11T15:51:09+00:00 Palmer Dabbelt palmer@sifive.com 2017-12-08T19:23:23+00:00 27b0174525325bf18919597016483a709f3372f8 This is code that probably should never have made it into the kernel in the first place: it depends on a driver that hadn't been reviewed yet. During the HVC_SBI_RISCV review process a better way of doing this was suggested, but that means this code is defunct. It's compile-time disabled in 4.15 because the driver isn't in, so I think it's safe to just remove this for now. CC: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com> 
This is code that probably should never have made it into the kernel in
the first place: it depends on a driver that hadn't been reviewed yet.
During the HVC_SBI_RISCV review process a better way of doing this was
suggested, but that means this code is defunct.  It's compile-time
disabled in 4.15 because the driver isn't in, so I think it's safe to
just remove this for now.

CC: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>