u-boot/arch/arm/mach-stm32mp/tzc400.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* Simple API for configuring TrustZone memory restrictions for TZC400
*/
#define LOG_CATEGORY LOGC_ARCH
#include <linux/iopoll.h>
#include <mach/tzc.h>
#define TZC_TIMEOUT_US 100
#define TZC_BUILD_CONFIG 0x00
#define TZC_ACTION 0x04
#define TZC_ACTION_NONE 0
#define TZC_ACTION_ERR 1
#define TZC_ACTION_INT 2
#define TZC_ACTION_INT_ERR 3
#define TZC_GATE_KEEPER 0x08
#define TZC_REGION0_OFFSET 0x100
#define TZC_REGION_CFG_SIZE 0x20
#define TZC_REGION1_OFFSET 0x120
#define TZC_REGION_BASE 0x00
#define TZC_REGION_TOP 0x08
#define TZC_REGION_ATTRIBUTE 0x10
#define TZC_REGION_ACCESS 0x14
static uint32_t tzc_read(uintptr_t tzc, size_t reg)
{
return readl(tzc + reg);
}
static void tzc_write(uintptr_t tzc, size_t reg, uint32_t val)
{
writel(val, tzc + reg);
}
static uint16_t tzc_config_get_active_filters(const struct tzc_region *cfg)
{
uint16_t active_filters = 0;
for ( ; cfg->top != 0; cfg++)
active_filters |= cfg->filters_mask;
return active_filters;
}
int tzc_configure(uintptr_t tzc, const struct tzc_region *cfg)
{
uintptr_t region = tzc + TZC_REGION1_OFFSET;
uint32_t nsid, attr_reg, active_filters;
int ret;
active_filters = tzc_config_get_active_filters(cfg);
if (active_filters == 0)
return -EINVAL;
ret = tzc_disable_filters(tzc, active_filters);
if (ret < 0)
return ret;
for ( ; cfg->top != 0; cfg++, region += TZC_REGION_CFG_SIZE) {
attr_reg = (cfg->sec_mode & 0x03) << 30;
attr_reg |= (cfg->filters_mask & 0x03) << 0;
nsid = cfg->nsec_id & 0xffff;
nsid |= nsid << 16;
tzc_write(region, TZC_REGION_BASE, cfg->base);
tzc_write(region, TZC_REGION_TOP, cfg->top);
tzc_write(region, TZC_REGION_ACCESS, nsid);
tzc_write(region, TZC_REGION_ATTRIBUTE, attr_reg);
}
tzc_write(tzc, TZC_ACTION, TZC_ACTION_ERR);
return tzc_enable_filters(tzc, active_filters);
}
int tzc_disable_filters(uintptr_t tzc, uint16_t filters_mask)
{
uint32_t gate = tzc_read(tzc, TZC_GATE_KEEPER);
uint32_t filter_status = filters_mask << 16;
gate &= ~filters_mask;
tzc_write(tzc, TZC_GATE_KEEPER, gate);
return readl_poll_timeout(tzc + TZC_GATE_KEEPER, gate,
(gate & filter_status) == 0, TZC_TIMEOUT_US);
}
int tzc_enable_filters(uintptr_t tzc, uint16_t filters_mask)
{
uint32_t gate = tzc_read(tzc, TZC_GATE_KEEPER);
uint32_t filter_status = filters_mask << 16;
gate |= filters_mask;
tzc_write(tzc, TZC_GATE_KEEPER, gate);
return readl_poll_timeout(tzc + TZC_GATE_KEEPER, gate,
(gate & filter_status) == filter_status,
TZC_TIMEOUT_US);
}
static const char *sec_access_str_from_attr(uint32_t attr)
{
const char *const sec_mode[] = { "none", "RO ", "WO ", "RW " };
return sec_mode[(attr >> 30) & 0x03];
}
void tzc_dump_config(uintptr_t tzc)
{
uint32_t build_config, base, top, attr, nsaid;
int num_regions, i;
uintptr_t region;
build_config = tzc_read(tzc, TZC_BUILD_CONFIG);
num_regions = ((build_config >> 0) & 0x1f) + 1;
for (i = 0; i < num_regions; i++) {
region = tzc + TZC_REGION0_OFFSET + i * TZC_REGION_CFG_SIZE;
base = tzc_read(region, TZC_REGION_BASE);
top = tzc_read(region, TZC_REGION_TOP);
attr = tzc_read(region, TZC_REGION_ATTRIBUTE);
nsaid = tzc_read(region, TZC_REGION_ACCESS);
if (attr == 0 && nsaid == 0)
continue;
log_info("TZC region %u: %08x->%08x - filters 0x%x\n",
i, base, top, (attr >> 0) & 0xf);
log_info("\t Secure access %s NSAID %08x\n",
sec_access_str_from_attr(attr), nsaid);
}
}