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gdrom_jvm_boot: use g1_if DMA

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This commit is contained in:
Zack Buhman 2025-01-01 12:31:01 -06:00
parent 540dec3299
commit 88a47068f2
1 changed files with 55 additions and 7 deletions
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62
example/gdrom_jvm_boot.cpp
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@ -35,6 +35,25 @@ void pio_data(const uint8_t * data)
while (gdrom::status::bsy(gdrom_if.status) != 0);
}
void dma_data(const uint8_t * data)
{
while ((gdrom::status::bsy(gdrom_if.status) | gdrom::status::drq(gdrom_if.status)) != 0);
gdrom_if.features = gdrom::features::dma::enable;
gdrom_if.drive_select = gdrom::drive_select::drive_select
| gdrom::drive_select::lun(0);
gdrom_if.command = gdrom::command::code::packet_command;
while (gdrom::status::drq(gdrom_if.status) == 0);
const uint16_t * buf = reinterpret_cast<const uint16_t *>(&data[0]);
for (int i = 0; i < 6; i++) {
gdrom_if.data = buf[i];
}
while (gdrom::status::bsy(gdrom_if.status) != 0);
}
void read_data(uint16_t * buf, const uint32_t length)
{
//serial::string("read_data drq interrupt_reason: ");
@ -105,6 +124,23 @@ uint32_t cd_read(uint16_t * buf,
return length;
}
void cd_read_dma(const uint32_t starting_address,
const uint32_t transfer_length)
{
const uint8_t data_select = 0b0010; // data
const uint8_t expected_data_type = 0b100; // XA mode 2 form 1
const uint8_t parameter_type = 0b0; // FAD specified
const uint8_t data = (data_select << 4) | (expected_data_type << 1) | (parameter_type << 0);
auto packet = gdrom_command_packet_format::cd_read(data,
starting_address,
transfer_length);
serial::string("cd_read\n");
serial::string("starting_address: ");
serial::integer<uint32_t>(starting_address);
dma_data(packet._data());
}
bool dr_is_self_or_parent(const iso9660::directory_record * dr)
{
if (dr->length_of_file_identifier != 1)
@ -143,13 +179,28 @@ void load_jvm_bin(const iso9660::directory_record * dr)
serial::string("load jvm bin:\n");
//__attribute__((aligned(4))) static uint16_t file_buf16[16384 / 2];
//uint32_t * file_buf32 = reinterpret_cast<uint32_t *>(file_buf16);
uint16_t * load_buf = reinterpret_cast<uint16_t *>(load_address);
int offset = 0;
int extent = dr->location_of_extent.get();
int data_length = dr->data_length.get();
serial::integer<uint32_t>(extent);
int sectors = ((data_length + 2047) / 2048);
data_length = sectors * 2048;
g1_if.GDAPRO = 0x8843407F;
g1_if.G1GDRC = 0x00001001;
g1_if.GDSTAR = load_address & ~(0b111 << 29);
g1_if.GDLEN = data_length;
g1_if.GDDIR = 1;
g1_if.GDEN = 1;
g1_if.GDST = 1;
cd_read_dma(extent + 150,
sectors);
serial::string("wait gdst");
while ((g1_if.GDST & 1) != 0);
/*
int transfers = 0;
while (data_length > 0) {
int transfer_size = min(data_length, 2048);
@ -168,6 +219,7 @@ void load_jvm_bin(const iso9660::directory_record * dr)
data_length -= sectors * 2048;
transfers += 1;
}
*/
serial::string("\njvm load complete\n");
jvm_load_complete = true;
@ -176,9 +228,6 @@ void load_jvm_bin(const iso9660::directory_record * dr)
serial::string("size: ");
serial::integer<uint32_t>(dr->data_length.get());
__data_length = dr->data_length.get();
serial::string("transfers: ");
serial::integer<uint32_t>(transfers);
}
void walk_directory_record(const iso9660::directory_record * dr)
@ -277,7 +326,6 @@ void main()
serial::integer<uint32_t>(jvm_load_complete);
if (jvm_load_complete) {
main_ptr_t jvm_main = reinterpret_cast<main_ptr_t>(load_address);
uint8_t * load_buf = reinterpret_cast<uint8_t *>(load_address);
serial::string("crc32: ");
int chunks = __data_length / 2048;