Add a few functions to permit reading of various useful base addresses provided by the hostbridge.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v1: - Add comments
arch/x86/cpu/apollolake/hostbridge.c | 27 ++++++++++++++++ .../include/asm/arch-apollolake/systemagent.h | 31 +++++++++++++++++++ 2 files changed, 58 insertions(+)
diff --git a/arch/x86/cpu/apollolake/hostbridge.c b/arch/x86/cpu/apollolake/hostbridge.c index cb46ec6c0bb..056f7e57a9a 100644 --- a/arch/x86/cpu/apollolake/hostbridge.c +++ b/arch/x86/cpu/apollolake/hostbridge.c @@ -40,7 +40,9 @@ enum {
PCIEXBAR_PCIEXBAREN = 1 << 0,
+ BGSM = 0xb4, /* Base GTT Stolen Memory */ TSEG = 0xb8, /* TSEG base */ + TOLUD = 0xbc, };
static int apl_hostbridge_early_init_pinctrl(struct udevice *dev) @@ -165,6 +167,31 @@ static int apl_hostbridge_probe(struct udevice *dev) return 0; }
+static ulong sa_read_reg(struct udevice *dev, int reg) +{ + u32 val; + + /* All regions concerned for have 1 MiB alignment */ + dm_pci_read_config32(dev, BGSM, &val); + + return ALIGN_DOWN(val, 1 << 20); +} + +ulong sa_get_tolud_base(struct udevice *dev) +{ + return sa_read_reg(dev, TOLUD); +} + +ulong sa_get_gsm_base(struct udevice *dev) +{ + return sa_read_reg(dev, BGSM); +} + +ulong sa_get_tseg_base(struct udevice *dev) +{ + return sa_read_reg(dev, TSEG); +} + static const struct udevice_id apl_hostbridge_ids[] = { { .compatible = "intel,apl-hostbridge" }, { } diff --git a/arch/x86/include/asm/arch-apollolake/systemagent.h b/arch/x86/include/asm/arch-apollolake/systemagent.h index 9e7bd62751a..788a63d7999 100644 --- a/arch/x86/include/asm/arch-apollolake/systemagent.h +++ b/arch/x86/include/asm/arch-apollolake/systemagent.h @@ -35,4 +35,35 @@ */ void enable_bios_reset_cpl(void);
+/** + * sa_get_tolud_base() - Get the TOLUD base address + * + * This returns the Top Of Low Useable DRAM, marking the top of usable DRAM + * below 4GB + * + * @dev: hostbridge device + * @return TOLUD address + */ +ulong sa_get_tolud_base(struct udevice *dev); + +/** + * sa_get_gsm_base() - Get the GSM base address + * + * This returns the base of GTT Stolen Memory, marking the start of memory used + * for Graphics Translation Tables. + * + * @dev: hostbridge device + * @return GSM address + */ +ulong sa_get_gsm_base(struct udevice *dev); + +/** + * sa_get_tseg_base() - Get the TSEG base address + * + * This returns the top address of DRAM available below 4GB + * + * @return TSEG base + */ +ulong sa_get_tseg_base(struct udevice *dev); + #endif