[binutils-gdb] ld: pru: Add optional section alignments

[binutils-gdb] ld: pru: Add optional section alignments

[Dimitar Dimitrov]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=ba268471bf9a2b76efc0d7a9c05291f7e8cd4424

commit ba268471bf9a2b76efc0d7a9c05291f7e8cd4424
Author: Dimitar Dimitrov <dimitar@dinux.eu>
Date:   Sun Jan 29 11:52:52 2023 +0200

    ld: pru: Add optional section alignments
    
    The Texas Instruments SoCs with AARCH64 host processors have stricter
    alignment requirements than ones with ARM32 host processors.  It's not
    only the requirement for resource_table to be aligned to 8.  But also
    any loadable segment size must be a multiple of 4 [1].
    
    The current PRU default linker script may output a segment size not
    aligned to 4, which would cause firmware load failure on AARCH64 hosts.
    
    Fix this by using COMMONPAGESIZE and MAXPAGESIZE to signify respectively
    the section memory size requirement and the resource table section's
    start address alignment.  This would avoid penalizing the ARM32 hosts,
    for which the default values (1 and 1) are sufficient.
    
    For AARCH64 hosts, the alignments would be overwritten from GCC spec
    files using the linker command line, e.g.:
      -z common-page-size=4 -z max-page-size=8
    
    [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/remoteproc/pru_rproc.c?h=v6.1#n555
    
    ld/ChangeLog:
    
            * scripttempl/pru.sc (_data_end): Remove the alignment.
            (.data): Align output section size to COMMONPAGESIZE.
            (.resource_table): Ditto.
    
    Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>

Diff:
---
 ld/scripttempl/pru.sc | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/ld/scripttempl/pru.sc b/ld/scripttempl/pru.sc
index 7cb80694641..4229bed99bb 100644
--- a/ld/scripttempl/pru.sc
+++ b/ld/scripttempl/pru.sc
@@ -147,7 +147,6 @@ SECTIONS
     ${RELOCATING+ *(.rodata:*)}
     ${RELOCATING+*(.gnu.linkonce.d*)}
     ${RELOCATING+*(.gnu.linkonce.r*)}
-    ${RELOCATING+. = ALIGN(4);}
     ${RELOCATING+ PROVIDE (_data_end = .) ; }
 
     ${RELOCATING+/* Merge the bss input sections into the output
@@ -164,13 +163,22 @@ SECTIONS
     ${RELOCATING+*(COMMON)}
     ${RELOCATING+ PROVIDE (_bss_end = .) ; }
 
+    ${RELOCATING+/* In case this is the last input section, align to
+      keep the loadable segment size a multiple of the common page size.
+      Some SoCs have stricter memory size requirements than others.  */
+    . = ALIGN (CONSTANT (COMMONPAGESIZE));}
   } ${RELOCATING+ > dmem}
 
   /* Linux remoteproc loader requires the resource_table section
-     start address to be aligned to 8 bytes.  */
-  .resource_table ${RELOCATING-0} ${RELOCATING+ ALIGN (8)} :
+     start address to be aligned to 8 bytes for SoCs with AARCH64
+     host processors.  */
+  .resource_table ${RELOCATING-0} ${RELOCATING+ ALIGN (CONSTANT (MAXPAGESIZE))} :
   {
     KEEP (*(.resource_table))
+    ${RELOCATING+/* In case this is the last input section, align to
+      keep the loadable segment size a multiple of the common page size.
+      Some SoCs have stricter memory size requirements than others.  */
+    . = ALIGN (CONSTANT (COMMONPAGESIZE));}
   } ${RELOCATING+ > dmem}
 
   /* Global data not cleared after reset.  */