remarkable-linux/include/linux/mbus.h
Thomas Petazzoni 4749c02b8d bus: mvebu-mbus: provide a mechanism to save SDRAM window configuration
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@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1416585613-2113-8-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-11-30 16:40:11 +00:00

80 lines
2.1 KiB
C

/*
* Marvell MBUS common definitions.
*
* Copyright (C) 2008 Marvell Semiconductor
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#ifndef __LINUX_MBUS_H
#define __LINUX_MBUS_H
struct resource;
struct mbus_dram_target_info
{
/*
* The 4-bit MBUS target ID of the DRAM controller.
*/
u8 mbus_dram_target_id;
/*
* The base address, size, and MBUS attribute ID for each
* of the possible DRAM chip selects. Peripherals are
* required to support at least 4 decode windows.
*/
int num_cs;
struct mbus_dram_window {
u8 cs_index;
u8 mbus_attr;
u32 base;
u32 size;
} cs[4];
};
/* Flags for PCI/PCIe address decoding regions */
#define MVEBU_MBUS_PCI_IO 0x1
#define MVEBU_MBUS_PCI_MEM 0x2
#define MVEBU_MBUS_PCI_WA 0x3
/*
* Magic value that explicits that we don't need a remapping-capable
* address decoding window.
*/
#define MVEBU_MBUS_NO_REMAP (0xffffffff)
/* Maximum size of a mbus window name */
#define MVEBU_MBUS_MAX_WINNAME_SZ 32
/*
* The Marvell mbus is to be found only on SOCs from the Orion family
* at the moment. Provide a dummy stub for other architectures.
*/
#ifdef CONFIG_PLAT_ORION
extern const struct mbus_dram_target_info *mv_mbus_dram_info(void);
#else
static inline const struct mbus_dram_target_info *mv_mbus_dram_info(void)
{
return NULL;
}
#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,
unsigned int attribute,
phys_addr_t base, size_t size,
phys_addr_t remap);
int mvebu_mbus_add_window_by_id(unsigned int target, unsigned int attribute,
phys_addr_t base, size_t size);
int mvebu_mbus_del_window(phys_addr_t base, size_t size);
int mvebu_mbus_init(const char *soc, phys_addr_t mbus_phys_base,
size_t mbus_size, phys_addr_t sdram_phys_base,
size_t sdram_size);
int mvebu_mbus_dt_init(bool is_coherent);
#endif /* __LINUX_MBUS_H */