[coreboot-gerrit] Change in coreboot[master]: nb/intel/i440bx: [WIP] Implement CBMEM in romstage

Keith Hui (Code Review) gerrit at coreboot.org
Sun Aug 13 04:35:57 CEST 2017


Keith Hui has uploaded this change for review. ( https://review.coreboot.org/20977


Change subject: nb/intel/i440bx: [WIP] Implement CBMEM in romstage
......................................................................

nb/intel/i440bx: [WIP] Implement CBMEM in romstage

An attempt to implement CBMEM in romstage.

Should benefit all 440BX boards but currently only being
tested on ASUS P2B-LS.

Currently does not boot and I need your help on the
mailing list.

Change-Id: I432f145a5343c1bb5f2b0de3b6b88f57124d1bd9
Signed-off-by: Keith Hui <buurin at gmail.com>
---
M src/northbridge/intel/i440bx/Kconfig
M src/northbridge/intel/i440bx/Makefile.inc
M src/northbridge/intel/i440bx/northbridge.c
A src/northbridge/intel/i440bx/ram_calc.c
4 files changed, 127 insertions(+), 2 deletions(-)



  git pull ssh://review.coreboot.org:29418/coreboot refs/changes/77/20977/1

diff --git a/src/northbridge/intel/i440bx/Kconfig b/src/northbridge/intel/i440bx/Kconfig
index 36d4754..45cdd9c 100644
--- a/src/northbridge/intel/i440bx/Kconfig
+++ b/src/northbridge/intel/i440bx/Kconfig
@@ -17,7 +17,6 @@
 	bool
 	select NO_MMCONF_SUPPORT
 	select HAVE_DEBUG_RAM_SETUP
-	select LATE_CBMEM_INIT
 	select UDELAY_IO
 
 config SDRAMPWR_4DIMM
diff --git a/src/northbridge/intel/i440bx/Makefile.inc b/src/northbridge/intel/i440bx/Makefile.inc
index ecefe6a..f900c50 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-y += ram_calc.c
 
 romstage-y += raminit.c
 romstage-y += debug.c
+romstage-y += ram_calc.c
 
 endif
diff --git a/src/northbridge/intel/i440bx/northbridge.c b/src/northbridge/intel/i440bx/northbridge.c
index dba7880..414ae99 100644
--- a/src/northbridge/intel/i440bx/northbridge.c
+++ b/src/northbridge/intel/i440bx/northbridge.c
@@ -67,7 +67,7 @@
 		ram_resource(dev, idx++, 0, 640);
 		ram_resource(dev, idx++, 768, tolmk - 768);
 
-		set_late_cbmem_top(tomk * 1024);
+		// 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 0000000..5e00545
--- /dev/null
+++ b/src/northbridge/intel/i440bx/ram_calc.c
@@ -0,0 +1,124 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2011 Google Inc.
+ * Copyright (C) 2012 ChromeOS Authors
+ * Copyright (C) 2017 Keith Hui <buurin at 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 <cpu/intel/romstage.h>
+#include <console/console.h>
+#include <cpu/x86/mtrr.h>
+#include <commonlib/helpers.h>
+#include "i440bx.h"
+
+unsigned long get_top_of_ram(void);
+
+unsigned long get_top_of_ram(void)
+{
+	return pci_read_config8(NB, DRB7) * 8 * MiB;
+}
+
+static unsigned long smm_region_start(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 = get_top_of_ram();
+
+	#if ENV_ROMSTAGE
+	/*
+	 * In romstage, gtom() above returns 0 if DRB7=0
+	 * (ie. RAM init isn't done).
+	 * Pass it on. This should not happen in ramstage.
+	 */
+	if (tom == 0)
+		return 0;
+	#endif
+
+	printk(BIOS_DEBUG, "get_top_of_ram() = %08lx", tom);
+
+	int tseg = pci_read_config8(NB, ESMRAMC) & 0x7; // H_SMRAM_EN and T_SZ
+	int gsmrame = pci_read_config8(NB, SMRAM) & 0x8; // G_SMRAME
+	if ((tseg & 0x1) && gsmrame) {
+		int tseg_size = 128 * KiB * (1 << (tseg >> 1));
+		tom -= tseg_size;
+	}
+	return tom;
+}
+
+void *cbmem_top(void)
+{
+	uintptr_t top_of_ram = ALIGN_DOWN(smm_region_start(), 4*MiB);
+	return (void *) top_of_ram;
+}
+
+#define ROMSTAGE_RAM_STACK_SIZE 0x5000
+/* setup_stack_and_mtrrs() determines the stack to use after
+ * cache-as-ram is torn down as well as the MTRR settings to use. */
+void *setup_stack_and_mtrrs(void)
+{
+	struct postcar_frame pcf;
+	uintptr_t tom;
+
+	if (postcar_frame_init(&pcf, ROMSTAGE_RAM_STACK_SIZE))
+		die("Unable to initialize postcar frame.\n");
+
+	/* Cache the ROM as WP just below 4GiB. */
+	postcar_frame_add_mtrr(&pcf, -CACHE_ROM_SIZE, CACHE_ROM_SIZE,
+		MTRR_TYPE_WRPROT);
+
+	/* Cache RAM as WB from 0 -> CACHE_TMP_RAMTOP. */
+	postcar_frame_add_mtrr(&pcf, 0, CACHE_TMP_RAMTOP, MTRR_TYPE_WRBACK);
+
+	/* Cache two separate 4 MiB regions below the top of ram, this
+	 * satisfies MTRR alignment requirements.
+	 */
+	tom = (uintptr_t)cbmem_top();
+	postcar_frame_add_mtrr(&pcf, tom - 4*MiB, 4*MiB, MTRR_TYPE_WRBACK);
+	postcar_frame_add_mtrr(&pcf, tom - 8*MiB, 4*MiB, MTRR_TYPE_WRBACK);
+
+	/* Save the number of MTRRs to setup. Return the stack location
+	 * pointing to the number of MTRRs.
+	 */
+	return postcar_commit_mtrrs(&pcf);
+}

-- 
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Gerrit-Project: coreboot
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: I432f145a5343c1bb5f2b0de3b6b88f57124d1bd9
Gerrit-Change-Number: 20977
Gerrit-PatchSet: 1
Gerrit-Owner: Keith Hui <buurin at gmail.com>
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