u-boot/board/renesas/rcar-common/common.c
Geert Uytterhoeven 33aca1c868 ARM: renesas: Propagate RPC-IF enablement to subsequent software
As the Renesas Reduced Pin Count Interface may be locked by TF-A, it is
disabled by default[1].  When unlocked, TF-A passes a DT fragment to
enable it, which is applied to the U-Boot DT[2].

Unlike the memory layout, the RPC-IF enablement is not propagated to
subsequent software.  Hence e.g. Linux cannot know if the RPC-IF is
locked or not, and will lock-up when trying to access the RPC-IF when
locked.

Fix this by checking if the RPC-IF is enabled in the TF-A DT fragment, and
setting the status of the RPC-IF device node in the target DT, if
present, to "okay".  Do this only when a "flash" subnode is found, to
avoid errors in subsequent software when the RPC-IF is not intended to
be used.

Note that this requires the status of the RPC-IF node to be set to
"disabled" in the target DT, just like in the U-Boot DT.

[1] commit 3d5f45c95c ("ARM: dts: rmobile: Disable RPC HF by
    default")
[2] commit 361377dbdb ("ARM: rmobile: Merge prior-stage firmware
    DT fragment into U-Boot DT on Gen3")

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2022-09-02 13:25:01 +02:00

168 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* board/renesas/rcar-common/common.c
*
* Copyright (C) 2013 Renesas Electronics Corporation
* Copyright (C) 2013 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
* Copyright (C) 2015 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
*/
#include <common.h>
#include <dm.h>
#include <fdt_support.h>
#include <init.h>
#include <asm/global_data.h>
#include <dm/uclass-internal.h>
#include <asm/arch/rmobile.h>
#include <linux/libfdt.h>
#ifdef CONFIG_RCAR_GEN3
DECLARE_GLOBAL_DATA_PTR;
/* If the firmware passed a device tree use it for e.g. U-Boot DRAM setup. */
extern u64 rcar_atf_boot_args[];
#define FDT_RPC_PATH "/soc/spi@ee200000"
int fdtdec_board_setup(const void *fdt_blob)
{
void *atf_fdt_blob = (void *)(rcar_atf_boot_args[1]);
if (fdt_magic(atf_fdt_blob) == FDT_MAGIC)
fdt_overlay_apply_node((void *)fdt_blob, 0, atf_fdt_blob, 0);
return 0;
}
int dram_init(void)
{
return fdtdec_setup_mem_size_base();
}
int dram_init_banksize(void)
{
fdtdec_setup_memory_banksize();
return 0;
}
#if defined(CONFIG_OF_BOARD_SETUP)
static int is_mem_overlap(void *blob, int first_mem_node, int curr_mem_node)
{
struct fdt_resource first_mem_res, curr_mem_res;
int curr_mem_reg, first_mem_reg = 0;
int ret;
for (;;) {
ret = fdt_get_resource(blob, first_mem_node, "reg",
first_mem_reg++, &first_mem_res);
if (ret) /* No more entries, no overlap found */
return 0;
curr_mem_reg = 0;
for (;;) {
ret = fdt_get_resource(blob, curr_mem_node, "reg",
curr_mem_reg++, &curr_mem_res);
if (ret) /* No more entries, check next tuple */
break;
if (curr_mem_res.end < first_mem_res.start)
continue;
if (curr_mem_res.start >= first_mem_res.end)
continue;
printf("Overlap found: 0x%llx..0x%llx / 0x%llx..0x%llx\n",
first_mem_res.start, first_mem_res.end,
curr_mem_res.start, curr_mem_res.end);
return 1;
}
}
return 0;
}
static void scrub_duplicate_memory(void *blob)
{
/*
* Scrub duplicate /memory@* node entries here. Some R-Car DTs might
* contain multiple /memory@* nodes, however fdt_fixup_memory_banks()
* either generates single /memory node or updates the first /memory
* node. Any remaining memory nodes are thus potential duplicates.
*
* However, it is not possible to delete all the memory nodes right
* away, since some of those might not be DRAM memory nodes, but some
* sort of other memory. Thus, delete only the memory nodes which are
* in the R-Car3 DBSC ranges.
*/
int mem = 0, first_mem_node = 0;
for (;;) {
mem = fdt_node_offset_by_prop_value(blob, mem,
"device_type", "memory", 7);
if (mem < 0)
break;
if (!fdtdec_get_is_enabled(blob, mem))
continue;
/* First memory node, patched by U-Boot */
if (!first_mem_node) {
first_mem_node = mem;
continue;
}
/* Check the remaining nodes and delete duplicates */
if (!is_mem_overlap(blob, first_mem_node, mem))
continue;
/* Delete duplicate node, start again */
fdt_del_node(blob, mem);
first_mem_node = 0;
mem = 0;
}
}
static void update_rpc_status(void *blob)
{
void *atf_fdt_blob = (void *)(rcar_atf_boot_args[1]);
int offset, enabled;
/*
* Check if the DT fragment received from TF-A had its RPC-IF device node
* enabled.
*/
if (fdt_magic(atf_fdt_blob) != FDT_MAGIC)
return;
offset = fdt_path_offset(atf_fdt_blob, FDT_RPC_PATH);
if (offset < 0)
return;
enabled = fdtdec_get_is_enabled(atf_fdt_blob, offset);
if (!enabled)
return;
/*
* Find the RPC-IF device node, and enable it if it has a flash subnode.
*/
offset = fdt_path_offset(blob, FDT_RPC_PATH);
if (offset < 0)
return;
if (fdt_subnode_offset(blob, offset, "flash") < 0)
return;
fdt_status_okay(blob, offset);
}
int ft_board_setup(void *blob, struct bd_info *bd)
{
scrub_duplicate_memory(blob);
update_rpc_status(blob);
return 0;
}
#endif
#endif