MIPS: Octeon: Add kexec and kdump support

[ralf@linux-mips.org: Original patch by Maxim Uvarov <muvarov@gmail.com>
with plenty of further shining, polishing, debugging and testing by me.]
Signed-off-by: Maxim Uvarov <muvarov@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: kexec@lists.infradead.org
Cc: horms@verge.net.au
Patchwork: https://patchwork.linux-mips.org/patch/1026/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/Makefile

@@ -192,6 +192,10 @@ endif
 #
 include $(srctree)/arch/mips/Kbuild.platforms
 
+ifdef CONFIG_PHYSICAL_START
+load-y                                  = $(CONFIG_PHYSICAL_START)
+endif
+
 cflags-y			+= -I$(srctree)/arch/mips/include/asm/mach-generic
 drivers-$(CONFIG_PCI)		+= arch/mips/pci/
 

arch/mips/cavium-octeon/executive/cvmx-bootmem.c

@@ -688,3 +688,8 @@ int64_t cvmx_bootmem_phy_named_block_alloc(uint64_t size, uint64_t min_addr,
 		cvmx_spinlock_unlock((cvmx_spinlock_t *)&(cvmx_bootmem_desc->lock));
 	return addr_allocated;
 }
+
+struct cvmx_bootmem_desc *cvmx_bootmem_get_desc(void)
+{
+	return cvmx_bootmem_desc;
+}

arch/mips/include/asm/octeon/cvmx-bootmem.h

@@ -370,4 +370,6 @@ void cvmx_bootmem_lock(void);
  */
 void cvmx_bootmem_unlock(void);
 
+extern struct cvmx_bootmem_desc *cvmx_bootmem_get_desc(void);
+
 #endif /*   __CVMX_BOOTMEM_H__ */

arch/mips/kernel/crash_dump.c

@@ -3,8 +3,6 @@
 #include <linux/crash_dump.h>
 #include <asm/uaccess.h>
 
-unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
-
 static int __init parse_savemaxmem(char *p)
 {
 	if (p)

arch/mips/kernel/relocate_kernel.S

@@ -78,7 +78,19 @@ done:
 	LONG_S		zero,(t0)
 #endif
 
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+	/* We need to flush I-cache before jumping to new kernel.
+	 * Unfortunatelly, this code is cpu-specific.
+	 */
+	.set push
+	.set noreorder
+	syncw
+	syncw
+	synci		0($0)
+	.set pop
+#else
 	sync
+#endif
 	/* jump to kexec_start_address */
 	j		s1
 	END(relocate_new_kernel)
@@ -110,7 +122,14 @@ LEAF(kexec_smp_wait)
 1:	LONG_L		s0, (t0)
 	bne		s0, zero,1b
 
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+	.set push
+	.set noreorder
+	synci		0($0)
+	.set pop
+#else
 	sync
+#endif
 	j		s1
 	END(kexec_smp_wait)
 #endif