powerpc/mpc83xx: Migrate from spd_sdram to unified DDR driver

Unified DDR driver is maintained for better performance, robustness and bug
fixes. Upgrading to use unified DDR driver for MPC83xx takes advantage of
overall improvement. It requires changes for board files to customize
platform-dependent parameters.

To utilize the unified DDR driver, a board needs to define CONFIG_FSL_DDRx
in the header file. No more boards will be accepted without such definition.

Note: the workaround for erratum DDR6 for the very old MPC834x Rev 1.0/1.1
and MPC8360 Rev 1.1/1.2 parts is not migrated to unified driver.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 61 insertions, 0 deletions

diff --git a/arch/powerpc/cpu/mpc83xx/law.c b/arch/powerpc/cpu/mpc83xx/law.c
new file mode 100644
index 0000000..66c88b6
--- /dev/null
+++ b/arch/powerpc/cpu/mpc83xx/law.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * Version 2 as published by the Free Software Foundation.
+ */
+
+#include <common.h>
+#include <asm/fsl_law.h>
+#include <asm/mmu.h>
+
+int set_ddr_laws(u64 start, u64 sz, enum law_trgt_if id)
+{
+	immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
+	law83xx_t *ecm = &immap->sysconf.ddrlaw[0];
+	u64 start_align, law_sz;
+	int law_sz_enc;
+
+	if (start == 0)
+		start_align = 1ull << (LAW_SIZE_2G + 1);
+	else
+		start_align = 1ull << (ffs64(start) - 1);
+	law_sz = min(start_align, sz);
+	law_sz_enc = __ilog2_u64(law_sz) - 1;
+
+	/*
+	 * Set up LAWBAR for all of DDR.
+	 */
+	ecm->bar = start & 0xfffff000;
+	ecm->ar  = (LAWAR_EN | (id << 20) | (LAWAR_SIZE & law_sz_enc));
+	debug("DDR:bar=0x%08x\n", ecm->bar);
+	debug("DDR:ar=0x%08x\n", ecm->ar);
+
+	/* recalculate size based on what was actually covered by the law */
+	law_sz = 1ull << __ilog2_u64(law_sz);
+
+	/* do we still have anything to map */
+	sz = sz - law_sz;
+	if (sz) {
+		start += law_sz;
+
+		start_align = 1ull << (ffs64(start) - 1);
+		law_sz = min(start_align, sz);
+		law_sz_enc = __ilog2_u64(law_sz) - 1;
+		ecm = &immap->sysconf.ddrlaw[1];
+		ecm->bar = start & 0xfffff000;
+		ecm->ar  = (LAWAR_EN | (id << 20) | (LAWAR_SIZE & law_sz_enc));
+		debug("DDR:bar=0x%08x\n", ecm->bar);
+		debug("DDR:ar=0x%08x\n", ecm->ar);
+	} else {
+		return 0;
+	}
+
+	/* do we still have anything to map */
+	sz = sz - law_sz;
+	if (sz)
+		return 1;
+
+	return 0;
+}