On Marvell EBU platforms, when doing suspend/resume, the SDRAM window
configuration must be saved on suspend, and restored on
resume. However, it needs to be restored on resume *before*
re-entering the kernel, because the SDRAM window configuration defines
the layout of the memory. For this reason, it cannot simply be done in
the ->suspend() and ->resume() hooks of the mvebu-mbus driver.
Instead, it needs to be restored by the bootloader "boot info"
mechanism used when resuming. This mechanism allows the kernel to
define a list of (address, value) pairs when suspending, that the
bootloader will restore on resume before jumping back into the kernel.
This commit therefore adds a new function to the mvebu-mbus driver,
called mvebu_mbus_save_cpu_target(), which will be called by the
platform code to make the mvebu-mbus driver save the SDRAM window
configuration in a way that can be understood by the bootloader "boot
info" mechanism.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
---
drivers/bus/mvebu-mbus.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/mbus.h | 1 +
2 files changed, 57 insertions(+)
diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
index 25b5b35..1d354e7 100644
--- a/drivers/bus/mvebu-mbus.c
+++ b/drivers/bus/mvebu-mbus.c
@@ -110,6 +110,8 @@ struct mvebu_mbus_soc_data {
bool has_mbus_bridge;
unsigned int (*win_cfg_offset)(const int win);
void (*setup_cpu_target)(struct mvebu_mbus_state *s);
+ int (*save_cpu_target)(struct mvebu_mbus_state *s,
+ u32 *store_addr);
int (*show_cpu_target)(struct mvebu_mbus_state *s,
struct seq_file *seq, void *v);
};
@@ -128,6 +130,7 @@ struct mvebu_mbus_state {
void __iomem *mbuswins_base;
void __iomem *sdramwins_base;
void __iomem *mbusbridge_base;
+ phys_addr_t sdramwins_phys_base;
struct dentry *debugfs_root;
struct dentry *debugfs_sdram;
struct dentry *debugfs_devs;
@@ -541,6 +544,28 @@ mvebu_mbus_default_setup_cpu_target(struct mvebu_mbus_state *mbus)
mvebu_mbus_dram_info.num_cs = cs;
}
+static int
+mvebu_mbus_default_save_cpu_target(struct mvebu_mbus_state *mbus,
+ u32 *store_addr)
+{
+ int i;
+
+ for (i = 0; i < 4; i++) {
+ u32 base = readl(mbus->sdramwins_base + DDR_BASE_CS_OFF(i));
+ u32 size = readl(mbus->sdramwins_base + DDR_SIZE_CS_OFF(i));
+
+ writel(mbus->sdramwins_phys_base + DDR_BASE_CS_OFF(i),
+ store_addr++);
+ writel(base, store_addr++);
+ writel(mbus->sdramwins_phys_base + DDR_SIZE_CS_OFF(i),
+ store_addr++);
+ writel(size, store_addr++);
+ }
+
+ /* We've written 16 words to the store address */
+ return 16;
+}
+
static void __init
mvebu_mbus_dove_setup_cpu_target(struct mvebu_mbus_state *mbus)
{
@@ -571,11 +596,35 @@ mvebu_mbus_dove_setup_cpu_target(struct mvebu_mbus_state *mbus)
mvebu_mbus_dram_info.num_cs = cs;
}
+static int
+mvebu_mbus_dove_save_cpu_target(struct mvebu_mbus_state *mbus,
+ u32 *store_addr)
+{
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ u32 map = readl(mbus->sdramwins_base + DOVE_DDR_BASE_CS_OFF(i));
+
+ writel(mbus->sdramwins_phys_base + DOVE_DDR_BASE_CS_OFF(i),
+ store_addr++);
+ writel(map, store_addr++);
+ }
+
+ /* We've written 4 words to the store address */
+ return 4;
+}
+
+int mvebu_mbus_save_cpu_target(u32 *store_addr)
+{
+ return mbus_state.soc->save_cpu_target(&mbus_state, store_addr);
+}
+
static const struct mvebu_mbus_soc_data armada_370_xp_mbus_data = {
.num_wins = 20,
.num_remappable_wins = 8,
.has_mbus_bridge = true,
.win_cfg_offset = armada_370_xp_mbus_win_offset,
+ .save_cpu_target = mvebu_mbus_default_save_cpu_target,
.setup_cpu_target = mvebu_mbus_default_setup_cpu_target,
.show_cpu_target = mvebu_sdram_debug_show_orion,
};
@@ -584,6 +633,7 @@ static const struct mvebu_mbus_soc_data kirkwood_mbus_data = {
.num_wins = 8,
.num_remappable_wins = 4,
.win_cfg_offset = orion_mbus_win_offset,
+ .save_cpu_target = mvebu_mbus_default_save_cpu_target,
.setup_cpu_target = mvebu_mbus_default_setup_cpu_target,
.show_cpu_target = mvebu_sdram_debug_show_orion,
};
@@ -592,6 +642,7 @@ static const struct mvebu_mbus_soc_data dove_mbus_data = {
.num_wins = 8,
.num_remappable_wins = 4,
.win_cfg_offset = orion_mbus_win_offset,
+ .save_cpu_target = mvebu_mbus_dove_save_cpu_target,
.setup_cpu_target = mvebu_mbus_dove_setup_cpu_target,
.show_cpu_target = mvebu_sdram_debug_show_dove,
};
@@ -604,6 +655,7 @@ static const struct mvebu_mbus_soc_data orion5x_4win_mbus_data = {
.num_wins = 8,
.num_remappable_wins = 4,
.win_cfg_offset = orion_mbus_win_offset,
+ .save_cpu_target = mvebu_mbus_default_save_cpu_target,
.setup_cpu_target = mvebu_mbus_default_setup_cpu_target,
.show_cpu_target = mvebu_sdram_debug_show_orion,
};
@@ -612,6 +664,7 @@ static const struct mvebu_mbus_soc_data orion5x_2win_mbus_data = {
.num_wins = 8,
.num_remappable_wins = 2,
.win_cfg_offset = orion_mbus_win_offset,
+ .save_cpu_target = mvebu_mbus_default_save_cpu_target,
.setup_cpu_target = mvebu_mbus_default_setup_cpu_target,
.show_cpu_target = mvebu_sdram_debug_show_orion,
};
@@ -620,6 +673,7 @@ static const struct mvebu_mbus_soc_data mv78xx0_mbus_data = {
.num_wins = 14,
.num_remappable_wins = 8,
.win_cfg_offset = mv78xx0_mbus_win_offset,
+ .save_cpu_target = mvebu_mbus_default_save_cpu_target,
.setup_cpu_target = mvebu_mbus_default_setup_cpu_target,
.show_cpu_target = mvebu_sdram_debug_show_orion,
};
@@ -805,6 +859,8 @@ static int __init mvebu_mbus_common_init(struct mvebu_mbus_state *mbus,
return -ENOMEM;
}
+ mbus->sdramwins_phys_base = sdramwins_phys_base;
+
if (mbusbridge_phys_base) {
mbus->mbusbridge_base = ioremap(mbusbridge_phys_base,
mbusbridge_size);
diff --git a/include/linux/mbus.h b/include/linux/mbus.h
index 550c88f..611b69f 100644
--- a/include/linux/mbus.h
+++ b/include/linux/mbus.h
@@ -61,6 +61,7 @@ static inline const struct mbus_dram_target_info *mv_mbus_dram_info(void)
}
#endif
+int mvebu_mbus_save_cpu_target(u32 *store_addr);
void mvebu_mbus_get_pcie_mem_aperture(struct resource *res);
void mvebu_mbus_get_pcie_io_aperture(struct resource *res);
int mvebu_mbus_add_window_remap_by_id(unsigned int target,
--
2.0.0
--
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