245 lines
9.7 KiB
C++

/*******************************************************************************
* Copyright (C) 2025 MINRES Technologies GmbH
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Contributors:
* eyck@minres.com - initial implementation
******************************************************************************/
#include "memory_if.h"
#include "iss/arch/riscv_hart_common.h"
#include "iss/vm_types.h"
#include <util/logging.h>
namespace iss {
namespace mem {
struct clic_config {
uint64_t clic_base{0xc0000000};
unsigned clic_int_ctl_bits{4};
unsigned clic_num_irq{16};
unsigned clic_num_trigger{0};
bool nmode{false};
};
inline void read_reg_with_offset(uint32_t reg, uint8_t offs, uint8_t* const data, unsigned length) {
auto reg_ptr = reinterpret_cast<uint8_t*>(&reg);
switch(offs) {
default:
for(auto i = 0U; i < length; ++i)
*(data + i) = *(reg_ptr + i);
break;
case 1:
for(auto i = 0U; i < length; ++i)
*(data + i) = *(reg_ptr + 1 + i);
break;
case 2:
for(auto i = 0U; i < length; ++i)
*(data + i) = *(reg_ptr + 2 + i);
break;
case 3:
*data = *(reg_ptr + 3);
break;
}
}
inline void write_reg_with_offset(uint32_t& reg, uint8_t offs, const uint8_t* const data, unsigned length) {
auto reg_ptr = reinterpret_cast<uint8_t*>(&reg);
switch(offs) {
default:
for(auto i = 0U; i < length; ++i)
*(reg_ptr + i) = *(data + i);
break;
case 1:
for(auto i = 0U; i < length; ++i)
*(reg_ptr + 1 + i) = *(data + i);
break;
case 2:
for(auto i = 0U; i < length; ++i)
*(reg_ptr + 2 + i) = *(data + i);
break;
case 3:
*(reg_ptr + 3) = *data;
break;
}
}
template <typename WORD_TYPE> struct pmp : public memory_elem {
using this_class = pmp<WORD_TYPE>;
using reg_t = WORD_TYPE;
constexpr static unsigned WORD_LEN = sizeof(WORD_TYPE) * 8;
pmp(arch::priv_if<WORD_TYPE> hart_if)
: hart_if(hart_if) {
for(size_t i = arch::pmpaddr0; i <= arch::pmpaddr15; ++i) {
hart_if.csr_rd_cb[i] = MK_CSR_RD_CB(read_plain);
hart_if.csr_wr_cb[i] = MK_CSR_WR_CB(write_plain);
}
for(size_t i = arch::pmpcfg0; i < arch::pmpcfg0 + 16 / sizeof(reg_t); ++i) {
hart_if.csr_rd_cb[i] = MK_CSR_RD_CB(read_plain);
hart_if.csr_wr_cb[i] = MK_CSR_WR_CB(write_pmpcfg);
}
}
virtual ~pmp() = default;
memory_if get_mem_if() override {
return memory_if{.rd_mem{util::delegate<rd_mem_func_sig>::from<this_class, &this_class::read_mem>(this)},
.wr_mem{util::delegate<wr_mem_func_sig>::from<this_class, &this_class::write_mem>(this)}};
}
void set_next(memory_if mem) override { down_stream_mem = mem; }
private:
iss::status read_mem(iss::access_type access, uint64_t addr, unsigned length, uint8_t* data) {
if(!pmp_check(access, addr, length) && !is_debug(access)) {
hart_if.fault_data = addr;
if(is_debug(access))
throw trap_access(0, addr);
hart_if.reg.trap_state = (1UL << 31) | ((access == access_type::FETCH ? 1 : 5) << 16); // issue trap 1
return iss::Err;
}
return down_stream_mem.rd_mem(access, addr, length, data);
}
iss::status write_mem(iss::access_type access, uint64_t addr, unsigned length, uint8_t const* data) {
if(!pmp_check(access, addr, length) && !is_debug(access)) {
hart_if.fault_data = addr;
if(is_debug(access))
throw trap_access(0, addr);
hart_if.reg.trap_state = (1UL << 31) | (7 << 16); // issue trap 1
return iss::Err;
}
return down_stream_mem.wr_mem(access, addr, length, data);
}
iss::status read_plain(unsigned addr, reg_t& val) {
val = hart_if.csr[addr];
return iss::Ok;
}
iss::status write_plain(unsigned addr, reg_t const& val) {
hart_if.csr[addr] = val;
return iss::Ok;
}
iss::status write_pmpcfg(unsigned addr, reg_t val) {
hart_if.csr[addr] = val & 0x9f9f9f9f;
return iss::Ok;
}
bool pmp_check(const access_type type, const uint64_t addr, const unsigned len);
protected:
arch::priv_if<WORD_TYPE> hart_if;
memory_if down_stream_mem;
};
template <typename WORD_TYPE> bool pmp<WORD_TYPE>::pmp_check(const access_type type, const uint64_t addr, const unsigned len) {
constexpr auto PMP_SHIFT = 2U;
constexpr auto PMP_R = 0x1U;
constexpr auto PMP_W = 0x2U;
constexpr auto PMP_X = 0x4U;
constexpr auto PMP_A = 0x18U;
constexpr auto PMP_L = 0x80U;
constexpr auto PMP_TOR = 0x1U;
constexpr auto PMP_NA4 = 0x2U;
constexpr auto PMP_NAPOT = 0x3U;
reg_t base = 0;
auto any_active = false;
auto const cfg_reg_size = sizeof(reg_t);
for(size_t i = 0; i < 16; i++) {
reg_t tor = hart_if.csr[arch::pmpaddr0 + i] << PMP_SHIFT;
uint8_t cfg = hart_if.csr[arch::pmpcfg0 + (i / cfg_reg_size)] >> (i % cfg_reg_size);
if(cfg & PMP_A) {
any_active = true;
auto pmp_a = (cfg & PMP_A) >> 3;
auto is_tor = pmp_a == PMP_TOR;
auto is_na4 = pmp_a == PMP_NA4;
reg_t mask = (hart_if.csr[arch::pmpaddr0 + i] << 1) | (!is_na4);
mask = ~(mask & ~(mask + 1)) << PMP_SHIFT;
// Check each 4-byte sector of the access
auto any_match = false;
auto all_match = true;
for(reg_t offset = 0; offset < len; offset += 1 << PMP_SHIFT) {
reg_t cur_addr = addr + offset;
auto napot_match = ((cur_addr ^ tor) & mask) == 0;
auto tor_match = base <= (cur_addr + len - 1) && cur_addr < tor;
auto match = is_tor ? tor_match : napot_match;
any_match |= match;
all_match &= match;
}
if(any_match) {
// If the PMP matches only a strict subset of the access, fail it
if(!all_match)
return false;
return (hart_if.reg.PRIV == arch::PRIV_M && !(cfg & PMP_L)) || (type == access_type::READ && (cfg & PMP_R)) ||
(type == access_type::WRITE && (cfg & PMP_W)) || (type == access_type::FETCH && (cfg & PMP_X));
}
}
base = tor;
}
// constexpr auto pmp_num_regs = 16;
// reg_t tor_base = 0;
// auto any_active = false;
// auto lower_addr = addr >>2;
// auto upper_addr = (addr+len-1)>>2;
// for (size_t i = 0; i < pmp_num_regs; i++) {
// uint8_t cfg = csr[pmpcfg0+(i/4)]>>(i%4);
// uint8_t cfg_next = i==(pmp_num_regs-1)? 0 : csr[pmpcfg0+((i+1)/4)]>>((i+1)%4);
// auto pmpaddr = csr[pmpaddr0+i];
// if (cfg & PMP_A) {
// any_active=true;
// auto is_tor = bit_sub<3, 2>(cfg) == PMP_TOR;
// auto is_napot = bit_sub<4, 1>(cfg) && bit_sub<3, 2>(cfg_next)!= PMP_TOR;
// if(is_napot) {
// reg_t mask = bit_sub<3, 1>(cfg)?~( pmpaddr & ~(pmpaddr + 1)): 0x3fffffff;
// auto mpmpaddr = pmpaddr & mask;
// if((lower_addr&mask) == mpmpaddr && (upper_addr&mask)==mpmpaddr)
// return (hart_if.reg.PRIV == PRIV_M && !(cfg & PMP_L)) ||
// (type == access_type::READ && (cfg & PMP_R)) ||
// (type == access_type::WRITE && (cfg & PMP_W)) ||
// (type == access_type::FETCH && (cfg & PMP_X));
// } else if(is_tor) {
// if(lower_addr>=tor_base && upper_addr<=pmpaddr)
// return (hart_if.reg.PRIV == PRIV_M && !(cfg & PMP_L)) ||
// (type == access_type::READ && (cfg & PMP_R)) ||
// (type == access_type::WRITE && (cfg & PMP_W)) ||
// (type == access_type::FETCH && (cfg & PMP_X));
// }
// }
// tor_base = pmpaddr;
// }
return !any_active || hart_if.reg.PRIV == arch::PRIV_M;
}
} // namespace mem
} // namespace iss