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* powerpc/asm: Convert .llong directives to .8byteTobin C. Harding2017-08-311-10/+10
| | | | | | | | | | | .llong is an undocumented PPC specific directive. The generic equivalent is .quad, but even better (because it's self describing) is .8byte. Convert all .llong directives to .8byte. Signed-off-by: Tobin C. Harding <me@tobin.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/boot: don't clobber r6 and r7 in epapr bootJeremy Kerr2015-03-161-12/+12
| | | | | | | | | | | We use r6 and r7 for epapr boot, but the current pre-C init will clobber both of these. This change does a simple replacement, of r6 -> r12 and r7 -> r13, so that we hit platform init with these registers intact. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/boot: Fix stack corruption in epapr entry pointJeremy Kerr2015-03-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, a 64-bit little-endian zImage.epapr won't boot in epapr mode, as we never return from platform_init. Before entering C, we initialise our stack by setting r1 16 bytes below the end of the _bss_stack: stwu r0,-16(r1) /* establish a stack frame */ However, the called function will save the caller's lr in the caller's frame's lr save area, at -16(r1) to -32(r1). This means that writes to the fdt variable will corrupt the saved link register: 0000000020c06018 l O .bss 0000000000001000 _bss_stack 0000000020c07018 l O .bss 0000000000000008 fdt We'll need at least 32 bytes in the initial stack frame, to handle the LR save area. We bump this to 112 bytes, as that'll be the max required by ABIv1. Thanks to Alistair Popple for debugging help. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/boot: Add support for 64bit little endian wrapperCédric Le Goater2014-04-281-0/+1
| | | | | | | | | | | | | | | | | | The code is only slightly modified : entry points now use the FIXUP_ENDIAN trampoline to switch endian order. The 32bit wrapper is kept for big endian kernels and 64bit is enforced for little endian kernels with a PPC64_BOOT_WRAPPER config option. The linker script is generated using the kernel preprocessor flags to make use of the CONFIG_* definitions and the wrapper script is modified to take into account the new elf64ppc format. Finally, the zImage file is compiled as a position independent executable (-pie) which makes it loadable at any address by the firmware. Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/boot: Modify entry point for 64bitCédric Le Goater2014-04-281-4/+104
| | | | | | | | | This patch adds support a 64bit wrapper entry point. As in 32bit, the entry point does its own relocation and can be loaded at any address by the firmware. Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/boot: Define a routine to enter promCédric Le Goater2014-04-281-0/+71
| | | | | | | | | | | | | This patch defines a 'prom' routine similar to 'enter_prom' in the kernel. The difference is in the MSR which is built before entering prom. Big endian order is enforced as in the kernel but 32bit mode is not. It prepares ground for the next patches which will introduce Little endian order. Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/boot: Allow building the zImage wrapper as a relocatable ET_DYNMichael Ellerman2011-04-201-42/+74
| | | | | | | | | | | | | | | | | | | This patch adds code, linker script and makefile support to allow building the zImage wrapper around the kernel as a position independent executable. This results in an ET_DYN instead of an ET_EXEC ELF output file, which can be loaded at any location by the firmware and will process its own relocations to work correctly at the loaded address. This is of interest particularly since the standard ePAPR image format must be an ET_DYN (although this patch alone is not sufficient to produce a fully ePAPR compliant boot image). Note for now we don't enable building with -pie for anything. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* [POWERPC] Fix building of COFF zImagesPaul Mackerras2007-06-071-0/+1
| | | | | | | | | The COFF zImage (for booting oldworld powermacs) wasn't being built correctly because the procedure descriptor in crt0.S for the zImage entry point wasn't declared as .globl, and therefore wasn't getting pulled in from wrapper.a by the linker. This adds the necessary .globl statement. Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] bootwrapper: missing relocation in crt0.SMilton Miller2007-04-131-2/+6
| | | | | | | | | crt0.S had provisions to provide run address relocaton to got2 and cache flush, but not on the bss clear or stack pointer load. Apply the same fixup for them. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] New reg.h for the zImageDavid Gibson2007-03-261-1/+0
| | | | | | | | | | | This patch adds a reg.h to the zImage code, with common definitions for accessing system registers. For now, this includes functions for retrieving the PVR and the stack pointer. This patch then uses the new reg.h to let start() display the running stack address without having to explicitly pass the stack as a parameter from the asm code. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] bootwrapper: Allow platforms to call library zImage_startMilton Miller2007-03-261-0/+2
| | | | | | | | | | Some platforms might need to run some code before the zImage start, but could otherwise use the bss clear and relocation code. Export the start address strongly as zImage_start_lib. Signed-off-by: Milton Miller <miltonm@bga.com> Acked-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] zImage: Cleanup and improve zImage entry pointDavid Gibson2007-03-131-3/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch re-organises the way the zImage wrapper code is entered, to allow more flexibility on platforms with unusual entry conditions. After this patch, a platform .o file has two options: 1) It can define a _zimage_start, in which case the platform code gets control from the very beginning of execution. In this case the platform code is responsible for relocating the zImage if necessary, clearing the BSS, performing any platform specific initialization, and finally calling start() to load and enter the kernel. 2) It can define platform_init(). In this case the generic crt0.S handles initial entry, and calls platform_init() before calling start(). The signature of platform_init() is changed, however, to take up to 5 parameters (in r3..r7) as they come from the platform's initial loader, instead of a fixed set of parameters based on OF's usage. When using the generic crt0.S, the platform .o can optionally supply a custom stack to use, using the BSS_STACK() macro. If this is not supplied, the crt0.S will assume that the loader has supplied a usable stack. In either case, the platform code communicates information to the generic code (specifically, a PROM pointer for OF systems, and/or an initrd image address supplied by the bootloader) via a global structure "loader_info". In addition the wrapper script is rearranged to ensure that the platform .o is always linked first. This means that platforms where the zImage entry point is at a fixed address or offset, rather than being encoded in the binary header can be supported using option (1). Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] powerpc: correct cacheflush loop in zImageOlaf Hering2006-03-161-2/+3
| | | | | | | | Correct the loop for cacheflush. No idea where I copied the code from, but the original does not work correct. Maybe the flush is not needed. Signed-off-by: Olaf Hering <olh@suse.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Make COFF zImages for old 32-bit powermacsPaul Mackerras2006-01-141-8/+13
| | | | | | | | | This adds code to build zImage.coff and/or zImage.initrd.coff when CONFIG_PPC32 and CONFIG_PPC_PMAC are defined. It also restructures the OF client code and adds some workarounds for OF quirks on the older machines. Signed-off-by: Paul Mackerras <paulus@samba.org>
* [PATCH] ppc boot: replace string labels with numbersOlaf Hering2005-11-181-12/+11
| | | | | | | | | | | Replacing the string labels with numbers saves 117 bytes in the final zImage. These local labels are not discared. Signed-off-by: Olaf Hering <olh@suse.de> arch/powerpc/boot/crt0.S | 23 +++++++++++------------ 1 files changed, 11 insertions(+), 12 deletions(-) Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Move ppc64 boot wrapper code over to arch/powerpcPaul Mackerras2005-11-161-0/+59
This also extends the code to handle 32-bit ELF vmlinux files as well as 64-bit ones. This is sufficient for booting on new-world 32-bit powermacs (i.e. all recent machines). Signed-off-by: Paul Mackerras <paulus@samba.org>