ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3

This adds the TCM interface to Linux, when active, it will
detect and report TCM memories and sizes early in boot if
present, introduce generic TCM memory handling, provide a
generic TCM memory pool and select TCM memory for the U300
platform.

See the Documentation/arm/tcm.txt for documentation.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 57 insertions, 0 deletions

diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 69371028a202..39d3ffb9ff2b 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -198,6 +198,63 @@ SECTIONS
         }
         _edata_loc = __data_loc + SIZEOF(.data);
 
+#ifdef CONFIG_HAVE_TCM
+        /*
+         * We align everything to a page boundary so we can
+         * free it after init has commenced and TCM contents have
+         * been copied to its destination.
+         */
+        .tcm_start : {
+                . = ALIGN(PAGE_SIZE);
+                __tcm_start = .;
+                __itcm_start = .;
+        }
+
+        /*
+         * Link these to the ITCM RAM
+         * Put VMA to the TCM address and LMA to the common RAM
+         * and we'll upload the contents from RAM to TCM and free
+         * the used RAM after that.
+         */
+        .text_itcm ITCM_OFFSET : AT(__itcm_start)
+        {
+                __sitcm_text = .;
+                *(.tcm.text)
+                *(.tcm.rodata)
+                . = ALIGN(4);
+                __eitcm_text = .;
+        }
+
+        /*
+         * Reset the dot pointer, this is needed to create the
+         * relative __dtcm_start below (to be used as extern in code).
+         */
+        . = ADDR(.tcm_start) + SIZEOF(.tcm_start) + SIZEOF(.text_itcm);
+
+        .dtcm_start : {
+                __dtcm_start = .;
+        }
+
+        /* TODO: add remainder of ITCM as well, that can be used for data! */
+        .data_dtcm DTCM_OFFSET : AT(__dtcm_start)
+        {
+                . = ALIGN(4);
+                __sdtcm_data = .;
+                *(.tcm.data)
+                . = ALIGN(4);
+                __edtcm_data = .;
+        }
+
+        /* Reset the dot pointer or the linker gets confused */
+        . = ADDR(.dtcm_start) + SIZEOF(.data_dtcm);
+
+        /* End marker for freeing TCM copy in linked object */
+        .tcm_end : AT(ADDR(.dtcm_start) + SIZEOF(.data_dtcm)){
+                . = ALIGN(PAGE_SIZE);
+                __tcm_end = .;
+        }
+#endif
+
         .bss : {
                 __bss_start = .;        /* BSS                          */
                 *(.bss)