[PATCH/RFC] FDPIC: add hook for arches to customize program header parsing

From: Mike Frysinger
Date: Fri Jun 12 2009 - 21:01:31 EST


From: Jie Zhang <jie.zhang@xxxxxxxxxx>

The Blackfin port has custom program header flags/addresses for
automatically loading regions into the dedicated on-chip SRAM. So add a
hook for ports to leverage.

Signed-off-by: Jie Zhang <jie.zhang@xxxxxxxxxx>
Signed-off-by: Mike Frysinger <vapier@xxxxxxxxxx>
CC: Bernd Schmidt <bernds_cb1@xxxxxxxxxxx>
---
arch/blackfin/include/asm/elf.h | 8 +++
arch/blackfin/kernel/Makefile | 1 +
arch/blackfin/kernel/binfmt_elf_fdpic.c | 80 +++++++++++++++++++++++++++++++
fs/binfmt_elf_fdpic.c | 7 +++
4 files changed, 96 insertions(+), 0 deletions(-)
create mode 100644 arch/blackfin/kernel/binfmt_elf_fdpic.c

diff --git a/arch/blackfin/include/asm/elf.h b/arch/blackfin/include/asm/elf.h
index 230e160..aba2506 100644
--- a/arch/blackfin/include/asm/elf.h
+++ b/arch/blackfin/include/asm/elf.h
@@ -124,4 +124,12 @@ do { \

#define SET_PERSONALITY(ex) set_personality(PER_LINUX)

+struct mm_struct;
+struct elf_fdpic_params;
+struct elf32_phdr;
+extern int elf_fdpic_plat_process_phdr(struct mm_struct *, struct elf_fdpic_params *,
+ struct elf32_phdr *, unsigned long *, unsigned long *);
+#define ELF_FDPIC_PLAT_PROCESS_PHDR(mm, params, phdr, maddr, disp) \
+ elf_fdpic_plat_process_phdr(mm, params, phdr, maddr, disp)
+
#endif
diff --git a/arch/blackfin/kernel/Makefile b/arch/blackfin/kernel/Makefile
index fd4d432..71c2291 100644
--- a/arch/blackfin/kernel/Makefile
+++ b/arch/blackfin/kernel/Makefile
@@ -15,6 +15,7 @@ else
obj-y += time.o
endif

+obj-$(CONFIG_BINFMT_ELF_FDPIC) += binfmt_elf_fdpic.o
obj-$(CONFIG_IPIPE) += ipipe.o
obj-$(CONFIG_IPIPE_TRACE_MCOUNT) += mcount.o
obj-$(CONFIG_BFIN_GPTIMERS) += gptimers.o
diff --git a/arch/blackfin/kernel/binfmt_elf_fdpic.c b/arch/blackfin/kernel/binfmt_elf_fdpic.c
new file mode 100644
index 0000000..d8192cf
--- /dev/null
+++ b/arch/blackfin/kernel/binfmt_elf_fdpic.c
@@ -0,0 +1,80 @@
+/*
+ * FDPIC ELF hooks
+ *
+ * Copyright (c) 2006-2009 Analog Devices Inc.
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/mm.h>
+#include <linux/elf.h>
+#include <linux/elf-fdpic.h>
+#include <linux/kernel.h>
+
+#include <asm/cacheflush.h>
+#include <asm/dma.h>
+
+int elf_fdpic_plat_process_phdr(struct mm_struct *mm,
+ struct elf_fdpic_params *params,
+ struct elf32_phdr *phdr,
+ unsigned long *maddr, unsigned long *disp)
+{
+ /* 0xfeb00000, 0xfec00000, 0xff700000, 0xff800000, 0xff900000
+ * and 0xffa00000 are also used in Dynamic linker and GNU ld.
+ * They need to be kept synchronized.
+ */
+ unsigned long flag = 0;
+ const char *type = NULL;
+
+ unsigned int e_flags = params->hdr.e_flags;
+ unsigned long p_vaddr = phdr->p_vaddr;
+ unsigned long p_flags = phdr->p_flags;
+
+ if (((e_flags & EF_BFIN_CODE_IN_L1) || p_vaddr == 0xffa00000) &&
+ (p_flags & (PF_W | PF_X)) == PF_X)
+ {
+ flag = L1_INST_SRAM;
+ type = "L1 instruction";
+
+ } else if (((e_flags & EF_BFIN_DATA_IN_L1) ||
+ p_vaddr == 0xff700000 ||
+ p_vaddr == 0xff800000 ||
+ p_vaddr == 0xff900000) &&
+ (p_flags & (PF_X | PF_W)) == PF_W)
+ {
+ if (p_vaddr == 0xff800000) {
+ flag = L1_DATA_A_SRAM;
+ type = "L1 Data A";
+ } else if (p_vaddr == 0xff900000) {
+ flag = L1_DATA_B_SRAM;
+ type = "L1 Data B";
+ } else {
+ flag = L1_DATA_SRAM;
+ type = "L1 Data";
+ }
+
+ } else if (p_vaddr == 0xfeb00000 || p_vaddr == 0xfec00000) {
+ flag = L2_SRAM;
+ type = "L2";
+ }
+
+ if (flag) {
+ void *sram_addr = sram_alloc_with_lsl(phdr->p_memsz, flag);
+ if (sram_addr == NULL) {
+ printk(KERN_ERR "elf_fdpic: not enough %s sram\n", type);
+ return -ENOMEM;
+ }
+
+ if (flag & L1_INST_SRAM)
+ safe_dma_memcpy(sram_addr, (const void *)(*maddr + *disp), phdr->p_memsz);
+ else
+ memcpy(sram_addr, (const void *)(*maddr + *disp), phdr->p_memsz);
+
+ down_write(&mm->mmap_sem);
+ do_munmap(mm, *maddr, phdr->p_memsz + *disp);
+ up_write(&mm->mmap_sem);
+ *maddr = (unsigned long)sram_addr;
+ *disp = 0;
+ }
+
+ return 0;
+}
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index fdb66fa..1bad16c 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1105,6 +1105,13 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
ELF_FDPIC_FLAG_CONTIGUOUS)
load_addr += PAGE_ALIGN(phdr->p_memsz + disp);

+#ifndef ELF_FDPIC_PLAT_PROCESS_PHDR
+# define ELF_FDPIC_PLAT_PROCESS_PHDR(mm, params, phdr, maddr, disp) 0
+#endif
+ ret = ELF_FDPIC_PLAT_PROCESS_PHDR(mm, params, phdr, &maddr, &disp);
+ if (ret)
+ return ret;
+
seg->addr = maddr + disp;
seg->p_vaddr = phdr->p_vaddr;
seg->p_memsz = phdr->p_memsz;
--
1.6.3.1

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