Rockbox open source high quality audio player as a Music Player Daemon
mpris
rockbox
mpd
libadwaita
audio
rust
zig
deno
Clean up .ncdata/ncbss hackery in plugin linker script
The mess here can be reduced by paying careful attention to
how the linker allocates LMAs/VMAs within MEMORY regions.
Changing the way .ncdata and .ncbss are defined so that they
reserve the LMA/VMA ranges they use in PLUGIN_RAM removes the
need to explicitly set the VMAs of other sections, cutting
down on the number of ifdefs needed and making the script a
bit simpler.
Change-Id: I316fc6e8dedd621537261d52c1ec7c20ec09438a
authored by
Aidan MacDonald
and committed by
Solomon Peachy
92b0bf7a
bce2c4e0
+47
-25
+47
-25
apps/plugins/plugin.lds
+47
-25
apps/plugins/plugin.lds
···
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} > PLUGIN_RAM
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#if NOCACHE_BASE != 0
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-
.ncdata . + NOCACHE_BASE :
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+
/*
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* Allocate .ncdata based on the following constraints:
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*
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* 1. the LMA must be allocated at the next free LMA in
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* PLUGIN_RAM and aligned to a cacheline boundary.
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* 2. the VMA - LMA offset must equal NOCACHE_BASE.
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*/
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.ncdata ALIGN(. + NOCACHE_BASE, CACHEALIGN_SIZE) : ALIGN(CACHEALIGN_SIZE)
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{
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. = ALIGN(CACHEALIGN_SIZE);
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*(.ncdata*)
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. = ALIGN(CACHEALIGN_SIZE);
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-
/* EABI currently needs these defined here, otherwise .iram and .bss can
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sometimes have an incorrect load address, breaking codecs and plugins. */
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bssaddr = . - NOCACHE_BASE;
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#if defined(IRAMSIZE) && IRAMSIZE != 0
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iramcopy = . - NOCACHE_BASE;
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-
#endif
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} AT> PLUGIN_RAM
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/* This definition is used when NOCACHE_BASE is 0. The address offset bug only
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seems to occur when the empty .ncdata is present. */
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#else
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bssaddr = .;
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#if defined(IRAMSIZE) && IRAMSIZE != 0
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iramcopy = .;
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-
#endif
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#endif
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/DISCARD/ :
···
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#endif
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}
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-
.bss bssaddr (NOLOAD) :
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+
.bss (NOLOAD) :
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{
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plugin_bss_start = .;
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_plugin_bss_start = .;
···
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} > PLUGIN_RAM
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#if NOCACHE_BASE != 0
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.ncbss . + NOCACHE_BASE (NOLOAD) :
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/*
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* .ncbss has the same constraints as the .ncdata section
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* above but there is an extra complication: because it is
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* a NOLOAD section, unlike .ncdata it cannot consume any
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* VMAs or LMAs in PLUGIN_RAM itself.
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*
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* Because free VMA/LMAs in PLUGIN_RAM are unchanged, any
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* subsequent sections will get placed at the end of the
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* .bss section, overlapping .ncbss, which we don't want.
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*
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* One solution is to manually place the next sections to
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* account for the size of .ncbss, but a cleaner solution
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* is to define a dummy section (.ncbss_vma) allocated at
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* the same VMA as .ncbss and equal in size, and placed in
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* the PLUGIN_RAM region. This allocates the correct VMA
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* range in plugin RAM so that the next section will not
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* overlap .ncbss.
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*/
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.ncbss ALIGN(. + NOCACHE_BASE, CACHEALIGN_SIZE) (NOLOAD) : ALIGN(CACHEALIGN_SIZE)
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{
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. = ALIGN(CACHEALIGN_SIZE);
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*(.ncbss*)
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. = ALIGN(CACHEALIGN_SIZE);
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/* We won't trust this one any more than with .ncdata */
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pluginendaddr = . - NOCACHE_BASE;
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} AT> PLUGIN_RAM
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#else
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pluginendaddr = .;
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+
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.ncbss_vma (NOLOAD) : ALIGN(CACHEALIGN_SIZE)
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{
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. += SIZEOF(.ncbss);
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} > PLUGIN_RAM
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#endif
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/* Final end of plugin after IRAM setup. The plugin or codec buffer
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is considered unused by the in-RAM image at this point once IRAM
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is copied. */
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.pluginend pluginendaddr :
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.pluginend (NOLOAD) :
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{
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_plugin_end_addr = .;
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plugin_end_addr = .;
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-
}
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} > PLUGIN_RAM
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#if defined(IRAMSIZE) && IRAMSIZE != 0
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.iram IRAMORIG : AT (iramcopy)
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.iram IRAMORIG : AT(LOADADDR(.bss))
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{
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iramstart = .;
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*(.icode)
···
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*(.idata)
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iramend = .;
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} > PLUGIN_IRAM
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+
iramcopy = LOADADDR(.iram);
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.ibss (NOLOAD) :
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{
···
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KEEP(*(.comment))
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}
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}
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+
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#if NOCACHE_BASE != 0
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/* Some asserts to make sure nocache sections appear correctly defined */
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ASSERT(LOADADDR(.ncdata) == ADDR(.ncdata) - NOCACHE_BASE, ".ncdata has incorrect LMA/VMA address");
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ASSERT(LOADADDR(.ncdata) % CACHEALIGN_SIZE == 0, ".ncdata incorrectly aligned");
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ASSERT(LOADADDR(.ncbss) == ADDR(.ncbss) - NOCACHE_BASE, ".ncbss has incorrect LMA/VMA address");
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ASSERT(LOADADDR(.ncbss) % CACHEALIGN_SIZE == 0, ".ncbss incorrectly aligned");
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ASSERT(ADDR(.ncbss_vma) == LOADADDR(.ncbss), ".ncbss_vma has wrong address");
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ASSERT(SIZEOF(.ncbss_vma) == SIZEOF(.ncbss), ".ncbss_vma has wrong size");
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#endif