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authorBin Meng <bmeng.cn@gmail.com>2015-02-02 22:35:26 +0800
committerSimon Glass <sjg@chromium.org>2015-02-06 12:07:41 -0700
commit0fae4d24df15b9133643c37e1a1d0d832fff801c (patch)
treef2d19033c7cd225d400d9c805a52d4860bd7377f /arch
parent3c8ae536ec26ffc7715e38876b43f88286a98fd8 (diff)
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x86: quark: Add Cache-As-RAM initialization
Quark SoC contains an embedded 512KiB SRAM (eSRAM) that is initialized by hardware. eSRAM is the ideal place to be used for Cache-As-RAM (CAR) before system memory is available. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Acked-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/cpu/quark/car.S105
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/x86/cpu/quark/car.S b/arch/x86/cpu/quark/car.S
new file mode 100644
index 0000000..3432ffa
--- /dev/null
+++ b/arch/x86/cpu/quark/car.S
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <config.h>
+#include <asm/pci.h>
+#include <asm/post.h>
+#include <asm/arch/quark.h>
+#include <asm/arch/msg_port.h>
+
+.globl car_init
+car_init:
+ post_code(POST_CAR_START)
+
+ /*
+ * Quark SoC contains an embedded 512KiB SRAM (eSRAM) that is
+ * initialized by hardware. eSRAM is the ideal place to be used
+ * for Cache-As-RAM (CAR) before system memory is available.
+ *
+ * Relocate this eSRAM to a suitable location in the physical
+ * memory map and enable it.
+ */
+
+ /* Host Memory Bound Register P03h:R08h */
+ mov $((MSG_PORT_HOST_BRIDGE << 16) | (HM_BOUND << 8)), %eax
+ mov $(DRAM_BASE + DRAM_MAX_SIZE + ESRAM_SIZE), %edx
+ lea 1f, %esp
+ jmp msg_port_write
+1:
+
+ /* eSRAM Block Page Control Register P05h:R82h */
+ mov $((MSG_PORT_MEM_MGR << 16) | (ESRAM_BLK_CTRL << 8)), %eax
+ mov $(ESRAM_BLOCK_MODE | (CONFIG_ESRAM_BASE >> 24)), %edx
+ lea 2f, %esp
+ jmp msg_port_write
+2:
+
+ post_code(POST_CAR_CPU_CACHE)
+ jmp car_init_ret
+
+msg_port_read:
+ /*
+ * Parameter:
+ * eax[23:16] - Message Port ID
+ * eax[15:08] - Register Address
+ *
+ * Return Value:
+ * eax - Message Port Register value
+ *
+ * Return Address: esp
+ */
+
+ or $((MSG_OP_READ << 24) | MSG_BYTE_ENABLE), %eax
+ mov %eax, %ebx
+
+ /* Write MCR B0:D0:F0:RD0 */
+ mov $(PCI_CFG_EN | MSG_CTRL_REG), %eax
+ mov $PCI_REG_ADDR, %dx
+ out %eax, %dx
+ mov $PCI_REG_DATA, %dx
+ mov %ebx, %eax
+ out %eax, %dx
+
+ /* Read MDR B0:D0:F0:RD4 */
+ mov $(PCI_CFG_EN | MSG_DATA_REG), %eax
+ mov $PCI_REG_ADDR, %dx
+ out %eax, %dx
+ mov $PCI_REG_DATA, %dx
+ in %dx, %eax
+
+ jmp *%esp
+
+msg_port_write:
+ /*
+ * Parameter:
+ * eax[23:16] - Message Port ID
+ * eax[15:08] - Register Address
+ * edx - Message Port Register value to write
+ *
+ * Return Address: esp
+ */
+
+ or $((MSG_OP_WRITE << 24) | MSG_BYTE_ENABLE), %eax
+ mov %eax, %esi
+ mov %edx, %edi
+
+ /* Write MDR B0:D0:F0:RD4 */
+ mov $(PCI_CFG_EN | MSG_DATA_REG), %eax
+ mov $PCI_REG_ADDR, %dx
+ out %eax, %dx
+ mov $PCI_REG_DATA, %dx
+ mov %edi, %eax
+ out %eax, %dx
+
+ /* Write MCR B0:D0:F0:RD0 */
+ mov $(PCI_CFG_EN | MSG_CTRL_REG), %eax
+ mov $PCI_REG_ADDR, %dx
+ out %eax, %dx
+ mov $PCI_REG_DATA, %dx
+ mov %esi, %eax
+ out %eax, %dx
+
+ jmp *%esp