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-rw-r--r--src/northbridge/intel/i440bx/Makefile.inc2
-rw-r--r--src/northbridge/intel/i440bx/northbridge.c3
-rw-r--r--src/northbridge/intel/i440bx/ram_calc.c64
3 files changed, 68 insertions, 1 deletions
diff --git a/src/northbridge/intel/i440bx/Makefile.inc b/src/northbridge/intel/i440bx/Makefile.inc
index 2e0092636a..50aeece1fe 100644
--- a/src/northbridge/intel/i440bx/Makefile.inc
+++ b/src/northbridge/intel/i440bx/Makefile.inc
@@ -17,8 +17,10 @@
ifeq ($(CONFIG_NORTHBRIDGE_INTEL_I440BX),y)
ramstage-y += northbridge.c
+ramstage-$(CONFIG_EARLY_CBMEM_INIT) += ram_calc.c
romstage-y += raminit.c
romstage-$(CONFIG_DEBUG_RAM_SETUP) += debug.c
+romstage-$(CONFIG_EARLY_CBMEM_INIT) += ram_calc.c
endif
diff --git a/src/northbridge/intel/i440bx/northbridge.c b/src/northbridge/intel/i440bx/northbridge.c
index dba7880d7f..8e5aa1191f 100644
--- a/src/northbridge/intel/i440bx/northbridge.c
+++ b/src/northbridge/intel/i440bx/northbridge.c
@@ -67,7 +67,8 @@ static void i440bx_domain_set_resources(device_t dev)
ram_resource(dev, idx++, 0, 640);
ram_resource(dev, idx++, 768, tolmk - 768);
- set_late_cbmem_top(tomk * 1024);
+ if (IS_ENABLED(CONFIG_LATE_CBMEM_INIT))
+ set_late_cbmem_top(tomk * 1024);
}
assign_resources(dev->link_list);
}
diff --git a/src/northbridge/intel/i440bx/ram_calc.c b/src/northbridge/intel/i440bx/ram_calc.c
new file mode 100644
index 0000000000..c9bfc2da9f
--- /dev/null
+++ b/src/northbridge/intel/i440bx/ram_calc.c
@@ -0,0 +1,64 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2017 Keith Hui <buurin@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define __SIMPLE_DEVICE__
+
+#include <arch/io.h>
+#include <cbmem.h>
+#include <commonlib/helpers.h>
+#include "i440bx.h"
+
+void *cbmem_top(void)
+{
+ /* Base of TSEG is top of usable DRAM */
+ /*
+ * SMRAM - System Management RAM Control Register
+ * 0x72
+ * [7:4] Not relevant to this function.
+ * [3:3] Global SMRAM Enable (G_SMRAME)
+ * [2:0] Hardwired to 010.
+ *
+ * ESMRAMC - Extended System Management RAM Control
+ * 0x73
+ * [7:7] H_SMRAM_EN
+ * 1 = When G_SMRAME=1, High SMRAM space is enabled at
+ * 0x100A0000-0x100FFFFF and forwarded to DRAM address
+ * 0x000A0000-0x000FFFFF.
+ * 0 = When G_SMRAME=1, Compatible SMRAM space is enabled at
+ * 0x000A0000-0x000BFFFF.
+ * [6:3] Not relevant to this function.
+ * [2:1] TSEG Size (T_SZ)
+ * Selects the size of the TSEG memory block, if enabled.
+ * 00 = 128KiB
+ * 01 = 256KiB
+ * 10 = 512KiB
+ * 11 = 1MiB
+ * [0:0] TSEG_EN
+ * When SMRAM[G_SMRAME] and this bit are 1, TSEG is enabled to
+ * appear between DRAM address (TOM-<TSEG Size>) to TOM.
+ *
+ * Source: 440BX datasheet, pages 3-28 thru 3-29.
+ */
+ unsigned long tom = pci_read_config8(NB, DRB7) * 8 * MiB;
+
+ int gsmrame = pci_read_config8(NB, SMRAM) & 0x8;
+ /* T_SZ and TSEG_EN */
+ int tseg = pci_read_config8(NB, ESMRAMC) & 0x7;
+ if ((tseg & 0x1) && gsmrame) {
+ int tseg_size = 128 * KiB * (1 << (tseg >> 1));
+ tom -= tseg_size;
+ }
+ return (void *)tom;
+}