pinephone-nuttx/display.zig
2022-10-09 10:44:41 +08:00

1028 lines
37 KiB
Zig
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

//***************************************************************************
//
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership. The
// ASF licenses this file to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance with the
// License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations
// under the License.
//
//***************************************************************************
//! PinePhone MIPI DSI Driver for Apache NuttX RTOS.
//! This MIPI DSI Interface is compatible with Zephyr MIPI DSI:
//! https://github.com/zephyrproject-rtos/zephyr/blob/main/include/zephyr/drivers/mipi_dsi.h
/// Import the Zig Standard Library
const std = @import("std");
/// Import the LoRaWAN Library from C
const c = @cImport({
// NuttX Defines
@cDefine("__NuttX__", "");
@cDefine("NDEBUG", "");
@cDefine("FAR", "");
// NuttX Header Files
@cInclude("arch/types.h");
@cInclude("../../nuttx/include/limits.h");
@cInclude("nuttx/config.h");
@cInclude("inttypes.h");
@cInclude("unistd.h");
@cInclude("stdlib.h");
@cInclude("stdio.h");
});
/// MIPI DSI Processor-to-Peripheral transaction types:
/// DCS Long Write. See https://lupyuen.github.io/articles/dsi#display-command-set-for-mipi-dsi
const MIPI_DSI_DCS_LONG_WRITE = 0x39;
/// DCS Short Write (Without Parameter)
const MIPI_DSI_DCS_SHORT_WRITE = 0x05;
/// DCS Short Write (With Parameter)
const MIPI_DSI_DCS_SHORT_WRITE_PARAM = 0x15;
const MIPI_DCS_EXIT_SLEEP_MODE = 0x11;
const MIPI_DCS_SET_DISPLAY_ON = 0x29;
/// Base Address of Allwinner A64 MIPI DSI Controller. See https://lupyuen.github.io/articles/dsi#a64-registers-for-mipi-dsi
const DSI_BASE_ADDRESS = 0x01CA_0000;
/// Instru_En is Bit 0 of DSI_BASIC_CTL0_REG
/// (DSI Configuration Register 0) at Offset 0x10
const DSI_BASIC_CTL0_REG = DSI_BASE_ADDRESS + 0x10;
const Instru_En = 1 << 0;
/// Initialise the ST7703 LCD Controller in Xingbangda XBD599 LCD Panel.
/// See https://lupyuen.github.io/articles/dsi#initialise-lcd-controller
pub export fn nuttx_panel_init() void {
debug("nuttx_panel_init", .{});
// Most of these commands are documented in the ST7703 Datasheet:
// https://files.pine64.org/doc/datasheet/pinephone/ST7703_DS_v01_20160128.pdf
writeDcs(&[_]u8 {
0xB9, // SETEXTC (Page 131): Enable USER Command
0xF1, // Enable User command
0x12, // (Continued)
0x83 // (Continued)
});
writeDcs(&[_]u8 {
0xBA, // SETMIPI (Page 144): Set MIPI related register
0x33, // Virtual Channel = 0 (VC_Main = 0) ; Number of Lanes = 4 (Lane_Number = 3)
0x81, // LDO = 1.7 V (DSI_LDO_SEL = 4) ; Terminal Resistance = 90 Ohm (RTERM = 1)
0x05, // MIPI Low High Speed driving ability = x6 (IHSRX = 5)
0xF9, // TXCLK speed in DSI LP mode = fDSICLK / 16 (Tx_clk_sel = 2)
0x0E, // Min HFP number in DSI mode = 14 (HFP_OSC = 14)
0x0E, // Min HBP number in DSI mode = 14 (HBP_OSC = 14)
0x20, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x44, // Undocumented
0x25, // Undocumented
0x00, // Undocumented
0x91, // Undocumented
0x0a, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x02, // Undocumented
0x4F, // Undocumented
0x11, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x37 // Undocumented
});
writeDcs(&[_]u8 {
0xB8, // SETPOWER_EXT (Page 142): Set display related register
0x25, // External power IC or PFM: VSP = FL1002, VSN = FL1002 (PCCS = 2) ; VCSW1 / VCSW2 Frequency for Pumping VSP / VSN = 1/4 Hsync (ECP_DC_DIV = 5)
0x22, // VCSW1/VCSW2 soft start time = 15 ms (DT = 2) ; Pumping ratio of VSP / VSN with VCI = x2 (XDK_ECP = 1)
0x20, // PFM operation frequency FoscD = Fosc/1 (PFM_DC_DIV = 0)
0x03 // Enable power IC pumping frequency synchronization = Synchronize with external Hsync (ECP_SYNC_EN = 1) ; Enable VGH/VGL pumping frequency synchronization = Synchronize with external Hsync (VGX_SYNC_EN = 1)
});
writeDcs(&[_]u8 {
0xB3, // SETRGBIF (Page 134): Control RGB I/F porch timing for internal use
0x10, // Vertical back porch HS number in Blank Frame Period = Hsync number 16 (VBP_RGB_GEN = 16)
0x10, // Vertical front porch HS number in Blank Frame Period = Hsync number 16 (VFP_RGB_GEN = 16)
0x05, // HBP OSC number in Blank Frame Period = OSC number 5 (DE_BP_RGB_GEN = 5)
0x05, // HFP OSC number in Blank Frame Period = OSC number 5 (DE_FP_RGB_GEN = 5)
0x03, // Undocumented
0xFF, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00, // Undocumented
0x00 // Undocumented
});
writeDcs(&[_]u8 {
0xC0, // SETSCR (Page 147): Set related setting of Source driving
0x73, // Source OP Amp driving period for positive polarity in Normal Mode: Source OP Period = 115*4/Fosc (N_POPON = 115)
0x73, // Source OP Amp driving period for negative polarity in Normal Mode: Source OP Period = 115*4/Fosc (N_NOPON = 115)
0x50, // Source OP Amp driving period for positive polarity in Idle mode: Source OP Period = 80*4/Fosc (I_POPON = 80)
0x50, // Source OP Amp dirivng period for negative polarity in Idle Mode: Source OP Period = 80*4/Fosc (I_NOPON = 80)
0x00, // (SCR Bits 24-31 = 0x00)
0xC0, // (SCR Bits 16-23 = 0xC0)
0x08, // Gamma bias current fine tune: Current xIbias = 4 (SCR Bits 9-13 = 4) ; (SCR Bits 8-15 = 0x08)
0x70, // Source and Gamma bias current core tune: Ibias = 1 (SCR Bits 0-3 = 0) ; Source bias current fine tune: Current xIbias = 7 (SCR Bits 4-8 = 7) ; (SCR Bits 0-7 = 0x70)
0x00 // Undocumented
});
writeDcs(&[_]u8 {
0xBC, // SETVDC (Page 146): Control NVDDD/VDDD Voltage
0x4E // NVDDD voltage = -1.8 V (NVDDD_SEL = 4) ; VDDD voltage = 1.9 V (VDDD_SEL = 6)
});
writeDcs(&[_]u8 {
0xCC, // SETPANEL (Page 154): Set display related register
0x0B // Enable reverse the source scan direction (SS_PANEL = 1) ; Normal vertical scan direction (GS_PANEL = 0) ; Normally black panel (REV_PANEL = 1) ; S1:S2:S3 = B:G:R (BGR_PANEL = 1)
});
writeDcs(&[_]u8 {
0xB4, // SETCYC (Page 135): Control display inversion type
0x80 // Extra source for Zig-Zag Inversion = S2401 (ZINV_S2401_EN = 1) ; Row source data dislocates = Even row (ZINV_G_EVEN_EN = 0) ; Disable Zig-Zag Inversion (ZINV_EN = 0) ; Enable Zig-Zag1 Inversion (ZINV2_EN = 0) ; Normal mode inversion type = Column inversion (N_NW = 0)
});
writeDcs(&[_]u8 {
0xB2, // SETDISP (Page 132): Control the display resolution
0xF0,
0x12,
0xF0
});
writeDcs(&[_]u8 {
0xE3, // SETEQ (Page 159): Set EQ related register
0x00,
0x00,
0x0B,
0x0B,
0x10,
0x10,
0x00,
0x00,
0x00,
0x00,
0xFF,
0x00,
0xC0,
0x10
});
writeDcs(&[_]u8 {
0xC6, // Undocumented
0x01, 0x00, 0xFF, 0xFF, 0x00
});
writeDcs(&[_]u8 {
0xC1, // SETPOWER (Page 149): Set related setting of power
0x74,
0x00,
0x32,
0x32,
0x77,
0xF1,
0xFF,
0xFF,
0xCC,
0xCC,
0x77,
0x77
});
writeDcs(&[_]u8 {
0xB5, // SETBGP (Page 136): Internal reference voltage setting
0x07,
0x07
});
writeDcs(&[_]u8 {
0xB6, // SETVCOM (Page 137): Set VCOM Voltage
0x2C,
0x2C
});
writeDcs(&[_]u8 {
0xBF, // Undocumented
0x02, 0x11, 0x00
});
writeDcs(&[_]u8 {
0xE9, // SETGIP1 (Page 163): Set forward GIP timing
0x82, 0x10, 0x06, 0x05, 0xA2, 0x0A, 0xA5, 0x12,
0x31, 0x23, 0x37, 0x83, 0x04, 0xBC, 0x27, 0x38,
0x0C, 0x00, 0x03, 0x00, 0x00, 0x00, 0x0C, 0x00,
0x03, 0x00, 0x00, 0x00, 0x75, 0x75, 0x31, 0x88,
0x88, 0x88, 0x88, 0x88, 0x88, 0x13, 0x88, 0x64,
0x64, 0x20, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88,
0x02, 0x88, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
});
writeDcs(&[_]u8 {
0xEA, // SETGIP2 (Page 170): Set backward GIP timing
0x02, 0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x02, 0x46, 0x02, 0x88,
0x88, 0x88, 0x88, 0x88, 0x88, 0x64, 0x88, 0x13,
0x57, 0x13, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88,
0x75, 0x88, 0x23, 0x14, 0x00, 0x00, 0x02, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x0A,
0xA5, 0x00, 0x00, 0x00, 0x00
});
writeDcs(&[_]u8 {
0xE0, // SETGAMMA (Page 158): Set the gray scale voltage to adjust the gamma characteristics of the TFT panel
0x00, 0x09, 0x0D, 0x23, 0x27, 0x3C, 0x41, 0x35,
0x07, 0x0D, 0x0E, 0x12, 0x13, 0x10, 0x12, 0x12,
0x18, 0x00, 0x09, 0x0D, 0x23, 0x27, 0x3C, 0x41,
0x35, 0x07, 0x0D, 0x0E, 0x12, 0x13, 0x10, 0x12,
0x12, 0x18
});
// TODO: Is this needed?
// SLPOUT (Page 89): Turns off sleep mode
writeDcs(&[_]u8 { MIPI_DCS_EXIT_SLEEP_MODE });
// TODO: Verify the delay
_ = c.usleep(120 * 1000);
// TODO: Is this needed?
// Display On (Page 97): Recover from DISPLAY OFF mode
writeDcs(&[_]u8 { MIPI_DCS_SET_DISPLAY_ON });
}
/// Write the DCS Command to MIPI DSI
fn writeDcs(buf: []const u8) void {
debug("writeDcs: len={}", .{ buf.len });
dump_buffer(&buf[0], buf.len);
assert(buf.len > 0);
// Do DCS Short Write or Long Write depending on command length
const res = switch (buf.len) {
// DCS Short Write (without parameter)
1 => nuttx_mipi_dsi_dcs_write(null, 0, MIPI_DSI_DCS_SHORT_WRITE,
&buf[0], buf.len),
// DCS Short Write (with parameter)
2 => nuttx_mipi_dsi_dcs_write(null, 0, MIPI_DSI_DCS_SHORT_WRITE_PARAM,
&buf[0], buf.len),
// DCS Long Write
else => nuttx_mipi_dsi_dcs_write(null, 0, MIPI_DSI_DCS_LONG_WRITE,
&buf[0], buf.len),
};
assert(res == buf.len);
}
/// Write to MIPI DSI. See https://lupyuen.github.io/articles/dsi#transmit-packet-over-mipi-dsi
pub export fn nuttx_mipi_dsi_dcs_write(
dev: [*c]const mipi_dsi_device, // MIPI DSI Host Device
channel: u8, // Virtual Channel ID
cmd: u8, // DCS Command
buf: [*c]const u8, // Transmit Buffer
len: usize // Buffer Length
) isize { // On Success: Return number of written bytes. On Error: Return negative error code
_ = dev;
debug("mipi_dsi_dcs_write: channel={}, cmd=0x{x}, len={}", .{ channel, cmd, len });
if (cmd == MIPI_DSI_DCS_SHORT_WRITE) { assert(len == 1); }
if (cmd == MIPI_DSI_DCS_SHORT_WRITE_PARAM) { assert(len == 2); }
// Allocate Packet Buffer
var pkt_buf = std.mem.zeroes([128]u8);
// Compose Short or Long Packet depending on DCS Command
const pkt = switch (cmd) {
// For DCS Long Write: Compose Long Packet
MIPI_DSI_DCS_LONG_WRITE =>
composeLongPacket(&pkt_buf, channel, cmd, buf, len),
// For DCS Short Write (with and without parameter):
// Compose Short Packet
MIPI_DSI_DCS_SHORT_WRITE,
MIPI_DSI_DCS_SHORT_WRITE_PARAM =>
composeShortPacket(&pkt_buf, channel, cmd, buf, len),
// DCS Command not supported
else => unreachable,
};
// Dump the packet
debug("packet: len={}", .{ pkt.len });
dump_buffer(&pkt[0], pkt.len);
// Set the following bits to 1 in DSI_CMD_CTL_REG (DSI Low Power Control Register) at Offset 0x200:
// RX_Overflow (Bit 26): Clear flag for "Receive Overflow"
// RX_Flag (Bit 25): Clear flag for "Receive has started"
// TX_Flag (Bit 9): Clear flag for "Transmit has started"
// All other bits must be set to 0.
const DSI_CMD_CTL_REG = DSI_BASE_ADDRESS + 0x200;
const RX_Overflow = 1 << 26;
const RX_Flag = 1 << 25;
const TX_Flag = 1 << 9;
putreg32(
RX_Overflow | RX_Flag | TX_Flag,
DSI_CMD_CTL_REG
);
// Write the Long Packet to DSI_CMD_TX_REG
// (DSI Low Power Transmit Package Register) at Offset 0x300 to 0x3FC
const DSI_CMD_TX_REG = DSI_BASE_ADDRESS + 0x300;
var addr: u64 = DSI_CMD_TX_REG;
var i: usize = 0;
while (i < pkt.len) : (i += 4) {
// Fetch the next 4 bytes, fill with 0 if not available
const b = [4]u32 {
pkt[i],
if (i + 1 < pkt.len) pkt[i + 1] else 0,
if (i + 2 < pkt.len) pkt[i + 2] else 0,
if (i + 3 < pkt.len) pkt[i + 3] else 0,
};
// Merge the next 4 bytes into a 32-bit value
const v: u32 =
b[0]
+ (b[1] << 8)
+ (b[2] << 16)
+ (b[3] << 24);
// Write the 32-bit value
assert(addr <= DSI_BASE_ADDRESS + 0x3FC);
modifyreg32(addr, 0xFFFF_FFFF, v);
addr += 4;
}
// Set Packet Length - 1 in Bits 0 to 7 (TX_Size) of
// DSI_CMD_CTL_REG (DSI Low Power Control Register) at Offset 0x200
modifyreg32(DSI_CMD_CTL_REG, 0xFF, @intCast(u32, pkt.len) - 1);
// Set DSI_INST_JUMP_SEL_REG (Offset 0x48, undocumented)
// to begin the Low Power Transmission (LPTX)
const DSI_INST_JUMP_SEL_REG = DSI_BASE_ADDRESS + 0x48;
const DSI_INST_ID_LPDT = 4;
const DSI_INST_ID_LP11 = 0;
const DSI_INST_ID_END = 15;
putreg32(
DSI_INST_ID_LPDT << (4 * DSI_INST_ID_LP11) |
DSI_INST_ID_END << (4 * DSI_INST_ID_LPDT),
DSI_INST_JUMP_SEL_REG
);
// Disable DSI Processing then Enable DSI Processing
disableDsiProcessing();
enableDsiProcessing();
// Wait for transmission to complete
const res = waitForTransmit();
if (res < 0) {
disableDsiProcessing();
return res;
}
// Return number of written bytes
return @intCast(isize, len);
}
/// Wait for transmit to complete. Returns 0 if completed, -1 if timeout.
/// See https://lupyuen.github.io/articles/dsi#transmit-packet-over-mipi-dsi
fn waitForTransmit() isize {
// Wait up to 5,000 microseconds
var i: usize = 0;
while (i < 5_000) : (i += 1) {
// To check whether the transmission is complete, we poll on Instru_En
if ((getreg32(DSI_BASIC_CTL0_REG) & Instru_En) == 0) {
// If Instru_En is 0, then transmission is complete
return 0;
}
// Sleep 1 microsecond
_ = c.usleep(1);
}
// Return Timeout
std.log.err("waitForTransmit: timeout", .{});
return -1;
}
/// Disable DSI Processing. See https://lupyuen.github.io/articles/dsi#transmit-packet-over-mipi-dsi
fn disableDsiProcessing() void {
// Set Instru_En to 0
modifyreg32(DSI_BASIC_CTL0_REG, Instru_En, 0);
}
/// Enable DSI Processing. See https://lupyuen.github.io/articles/dsi#transmit-packet-over-mipi-dsi
fn enableDsiProcessing() void {
// Set Instru_En to 1
modifyreg32(DSI_BASIC_CTL0_REG, Instru_En, Instru_En);
}
// Compose MIPI DSI Long Packet. See https://lupyuen.github.io/articles/dsi#long-packet-for-mipi-dsi
fn composeLongPacket(
pkt: []u8, // Buffer for the Long Packet
channel: u8, // Virtual Channel ID
cmd: u8, // DCS Command
buf: [*c]const u8, // Transmit Buffer
len: usize // Buffer Length
) []const u8 { // Returns the Long Packet
debug("composeLongPacket: channel={}, cmd=0x{x}, len={}", .{ channel, cmd, len });
// Data Identifier (DI) (1 byte):
// - Virtual Channel Identifier (Bits 6 to 7)
// - Data Type (Bits 0 to 5)
// (Virtual Channel should be 0, I think)
assert(channel < 4);
assert(cmd < (1 << 6));
const vc: u8 = channel;
const dt: u8 = cmd;
const di: u8 = (vc << 6) | dt;
// Word Count (WC) (2 bytes)
// - Number of bytes in the Packet Payload
const wc: u16 = @intCast(u16, len);
const wcl: u8 = @intCast(u8, wc & 0xff);
const wch: u8 = @intCast(u8, wc >> 8);
// Data Identifier + Word Count (3 bytes): For computing Error Correction Code (ECC)
const di_wc = [3]u8 { di, wcl, wch };
// Compute Error Correction Code (ECC) for Data Identifier + Word Count
const ecc: u8 = computeEcc(di_wc);
// Packet Header (4 bytes):
// - Data Identifier + Word Count + Error Correction COde
const header = [4]u8 { di_wc[0], di_wc[1], di_wc[2], ecc };
// Packet Payload:
// - Data (0 to 65,541 bytes):
// Number of data bytes should match the Word Count (WC)
assert(len <= 65_541);
const payload = buf[0..len];
// Checksum (CS) (2 bytes):
// - 16-bit Cyclic Redundancy Check (CRC) of the Payload (not the entire packet)
const cs: u16 = computeCrc(payload);
const csl: u8 = @intCast(u8, cs & 0xff);
const csh: u8 = @intCast(u8, cs >> 8);
// Packet Footer (2 bytes)
// - Checksum (CS)
const footer = [2]u8 { csl, csh };
// Packet:
// - Packet Header (4 bytes)
// - Payload (`len` bytes)
// - Packet Footer (2 bytes)
const pktlen = header.len + len + footer.len;
assert(pktlen <= pkt.len); // Increase `pkt` size
std.mem.copy(u8, pkt[0..header.len], &header); // 4 bytes
std.mem.copy(u8, pkt[header.len..], payload); // `len` bytes
std.mem.copy(u8, pkt[(header.len + len)..], &footer); // 2 bytes
// Return the packet
const result = pkt[0..pktlen];
return result;
}
// Compose MIPI DSI Short Packet. See https://lupyuen.github.io/articles/dsi#appendix-short-packet-for-mipi-dsi
fn composeShortPacket(
pkt: []u8, // Buffer for the Long Packet
channel: u8, // Virtual Channel ID
cmd: u8, // DCS Command
buf: [*c]const u8, // Transmit Buffer
len: usize // Buffer Length
) []const u8 { // Returns the Short Packet
debug("composeShortPacket: channel={}, cmd=0x{x}, len={}", .{ channel, cmd, len });
assert(len == 1 or len == 2);
// From BL808 Reference Manual (Page 201): https://github.com/sipeed/sipeed2022_autumn_competition/blob/main/assets/BL808_RM_en.pdf
// A Short Packet consists of 8-bit data identification (DI),
// two bytes of commands or data, and 8-bit ECC.
// The length of a short packet is 4 bytes including ECC.
// Thus a MIPI DSI Short Packet (compared with Long Packet)...
// - Doesn't have Packet Payload and Packet Footer (CRC)
// - Instead of Word Count (WC), the Packet Header now has 2 bytes of data
// Everything else is the same.
// Data Identifier (DI) (1 byte):
// - Virtual Channel Identifier (Bits 6 to 7)
// - Data Type (Bits 0 to 5)
// (Virtual Channel should be 0, I think)
assert(channel < 4);
assert(cmd < (1 << 6));
const vc: u8 = channel;
const dt: u8 = cmd;
const di: u8 = (vc << 6) | dt;
// Data (2 bytes), fill with 0 if Second Byte is missing
const data = [2]u8 {
buf[0], // First Byte
if (len == 2) buf[1] else 0, // Second Byte
};
// Data Identifier + Data (3 bytes): For computing Error Correction Code (ECC)
const di_data = [3]u8 { di, data[0], data[1] };
// Compute Error Correction Code (ECC) for Data Identifier + Word Count
const ecc: u8 = computeEcc(di_data);
// Packet Header (4 bytes):
// - Data Identifier + Word Count + Error Correction COde
const header = [4]u8 { di_data[0], di_data[1], di_data[2], ecc };
// Packet:
// - Packet Header (4 bytes)
const pktlen = header.len;
assert(pktlen <= pkt.len); // Increase `pkt` size
std.mem.copy(u8, pkt[0..header.len], &header); // 4 bytes
// Return the packet
const result = pkt[0..pktlen];
return result;
}
/// Compute the Error Correction Code (ECC) (1 byte):
/// Allow single-bit errors to be corrected and 2-bit errors to be detected in the Packet Header
/// See "12.3.6.12: Error Correction Code", Page 208 of BL808 Reference Manual:
/// https://github.com/sipeed/sipeed2022_autumn_competition/blob/main/assets/BL808_RM_en.pdf
fn computeEcc(
di_wc: [3]u8 // Data Identifier + Word Count (3 bytes)
) u8 {
// Combine DI and WC into a 24-bit word
var di_wc_word: u32 =
di_wc[0]
| (@intCast(u32, di_wc[1]) << 8)
| (@intCast(u32, di_wc[2]) << 16);
// Extract the 24 bits from the word
var d = std.mem.zeroes([24]u1);
var i: usize = 0;
while (i < 24) : (i += 1) {
d[i] = @intCast(u1, di_wc_word & 1);
di_wc_word >>= 1;
}
// Compute the ECC bits
var ecc = std.mem.zeroes([8]u1);
ecc[7] = 0;
ecc[6] = 0;
ecc[5] = d[10] ^ d[11] ^ d[12] ^ d[13] ^ d[14] ^ d[15] ^ d[16] ^ d[17] ^ d[18] ^ d[19] ^ d[21] ^ d[22] ^ d[23];
ecc[4] = d[4] ^ d[5] ^ d[6] ^ d[7] ^ d[8] ^ d[9] ^ d[16] ^ d[17] ^ d[18] ^ d[19] ^ d[20] ^ d[22] ^ d[23];
ecc[3] = d[1] ^ d[2] ^ d[3] ^ d[7] ^ d[8] ^ d[9] ^ d[13] ^ d[14] ^ d[15] ^ d[19] ^ d[20] ^ d[21] ^ d[23];
ecc[2] = d[0] ^ d[2] ^ d[3] ^ d[5] ^ d[6] ^ d[9] ^ d[11] ^ d[12] ^ d[15] ^ d[18] ^ d[20] ^ d[21] ^ d[22];
ecc[1] = d[0] ^ d[1] ^ d[3] ^ d[4] ^ d[6] ^ d[8] ^ d[10] ^ d[12] ^ d[14] ^ d[17] ^ d[20] ^ d[21] ^ d[22] ^ d[23];
ecc[0] = d[0] ^ d[1] ^ d[2] ^ d[4] ^ d[5] ^ d[7] ^ d[10] ^ d[11] ^ d[13] ^ d[16] ^ d[20] ^ d[21] ^ d[22] ^ d[23];
// Merge the ECC bits
return @intCast(u8, ecc[0])
| (@intCast(u8, ecc[1]) << 1)
| (@intCast(u8, ecc[2]) << 2)
| (@intCast(u8, ecc[3]) << 3)
| (@intCast(u8, ecc[4]) << 4)
| (@intCast(u8, ecc[5]) << 5)
| (@intCast(u8, ecc[6]) << 6)
| (@intCast(u8, ecc[7]) << 7);
}
/// Compute 16-bit Cyclic Redundancy Check (CRC).
/// See "12.3.6.13: Packet Footer", Page 210 of BL808 Reference Manual:
/// https://github.com/sipeed/sipeed2022_autumn_competition/blob/main/assets/BL808_RM_en.pdf
fn computeCrc(
data: []const u8
) u16 {
// Use CRC-16-CCITT (x^16 + x^12 + x^5 + 1)
const crc = crc16ccitt(data, 0xffff);
// debug("computeCrc: len={}, crc=0x{x}", .{ data.len, crc });
// dump_buffer(&data[0], data.len);
return crc;
}
/// Return a 16-bit CRC-CCITT of the contents of the `src` buffer.
/// Based on https://github.com/lupyuen/incubator-nuttx/blob/pinephone/libs/libc/misc/lib_crc16.c
fn crc16ccitt(src: []const u8, crc16val: u16) u16 {
var i: usize = 0;
var v = crc16val;
while (i < src.len) : (i += 1) {
v = (v >> 8)
^ crc16ccitt_tab[(v ^ src[i]) & 0xff];
}
return v;
}
/// From CRC-16-CCITT (x^16 + x^12 + x^5 + 1)
const crc16ccitt_tab = [256]u16 {
0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78,
};
/// Atomically modify the specified bits in a memory mapped register.
/// Based on https://github.com/lupyuen/incubator-nuttx/blob/pinephone/arch/arm/src/common/arm_modifyreg32.c#L38-L57
fn modifyreg32(
addr: u64, // Address to modify
clearbits: u32, // Bits to clear, like (1 << bit)
setbits: u32 // Bit to set, like (1 << bit)
) void {
debug("modifyreg32: addr=0x{x:0>3}, val=0x{x:0>8}", .{ addr - DSI_BASE_ADDRESS, setbits & clearbits });
// TODO: flags = spin_lock_irqsave(NULL);
var regval = getreg32(addr);
regval &= ~clearbits;
regval |= setbits;
putreg32(regval, addr);
// TODO: spin_unlock_irqrestore(NULL, flags);
}
/// Get the 32-bit value at the address
fn getreg32(addr: u64) u32 {
const ptr = @intToPtr(*const volatile u32, addr);
return ptr.*;
}
/// Set the 32-bit value at the address
fn putreg32(val: u32, addr: u64) void {
const ptr = @intToPtr(*volatile u32, addr);
ptr.* = val;
}
///////////////////////////////////////////////////////////////////////////////
// MIPI DSI Types
/// MIPI DSI Device
pub const mipi_dsi_device = extern struct {
/// Number of Data Lanes
data_lanes: u8,
/// Display Timings
timings: mipi_dsi_timings,
/// Pixel Format
pixfmt: u32,
/// Mode Flags
mode_flags: u32,
};
/// MIPI DSI Read / Write Message
pub const mipi_dsi_msg = extern struct {
/// Payload Data Type
type: u8,
/// Flags controlling message transmission
flags: u16,
/// Command (only for DCS)
cmd: u8,
/// Transmit Buffer Length
tx_len: usize,
/// Transmit Buffer
tx_buf: [*c]const u8,
/// Receive Buffer Length
rx_len: usize,
/// Receive Buffer
rx_buf: [*c]u8,
};
/// MIPI DSI Display Timings
pub const mipi_dsi_timings = extern struct {
/// Horizontal active video
hactive: u32,
/// Horizontal front porch
hfp: u32,
/// Horizontal back porch
hbp: u32,
/// Horizontal sync length
hsync: u32,
/// Vertical active video
vactive: u32,
/// Vertical front porch
vfp: u32,
/// Vertical back porch
vbp: u32,
/// Vertical sync length
vsync: u32,
};
///////////////////////////////////////////////////////////////////////////////
// Test Functions
/// Main Function for Null App
pub export fn null_main(_argc: c_int, _argv: [*]const [*]const u8) c_int {
_ = _argc;
_ = _argv;
test_zig();
return 0;
}
/// Zig Test Function
pub export fn test_zig() void {
_ = printf("HELLO ZIG ON PINEPHONE!\n");
// Allocate Packet Buffer
var pkt_buf = std.mem.zeroes([128]u8);
// Test Compose Short Packet (Without Parameter)
debug("Testing Compose Short Packet (Without Parameter)...", .{});
const short_pkt = [_]u8 {
0x11,
};
const short_pkt_result = composeShortPacket(
&pkt_buf, // Packet Buffer
0, // Virtual Channel
MIPI_DSI_DCS_SHORT_WRITE, // DCS Command
&short_pkt, // Transmit Buffer
short_pkt.len // Buffer Length
);
debug("Result:", .{});
dump_buffer(&short_pkt_result[0], short_pkt_result.len);
assert( // Verify result
std.mem.eql(
u8,
short_pkt_result,
&[_]u8 {
0x05, 0x11, 0x00, 0x36
}
)
);
// Write to MIPI DSI
// _ = nuttx_mipi_dsi_dcs_write(
// null, // Device
// 0, // Virtual Channel
// MIPI_DSI_DCS_SHORT_WRITE, // DCS Command
// &short_pkt, // Transmit Buffer
// short_pkt.len // Buffer Length
// );
// Test Compose Short Packet (With Parameter)
debug("Testing Compose Short Packet (With Parameter)...", .{});
const short_pkt_param = [_]u8 {
0xbc, 0x4e,
};
const short_pkt_param_result = composeShortPacket(
&pkt_buf, // Packet Buffer
0, // Virtual Channel
MIPI_DSI_DCS_SHORT_WRITE_PARAM, // DCS Command
&short_pkt_param, // Transmit Buffer
short_pkt_param.len // Buffer Length
);
debug("Result:", .{});
dump_buffer(&short_pkt_param_result[0], short_pkt_param_result.len);
assert( // Verify result
std.mem.eql(
u8,
short_pkt_param_result,
&[_]u8 {
0x15, 0xbc, 0x4e, 0x35
}
)
);
// Write to MIPI DSI
// _ = nuttx_mipi_dsi_dcs_write(
// null, // Device
// 0, // Virtual Channel
// MIPI_DSI_DCS_SHORT_WRITE_PARAM, // DCS Command
// &short_pkt_param, // Transmit Buffer
// short_pkt_param.len // Buffer Length
// );
// Test Compose Long Packet
debug("Testing Compose Long Packet...", .{});
const long_pkt = [_]u8 {
0xe9, 0x82, 0x10, 0x06, 0x05, 0xa2, 0x0a, 0xa5,
0x12, 0x31, 0x23, 0x37, 0x83, 0x04, 0xbc, 0x27,
0x38, 0x0c, 0x00, 0x03, 0x00, 0x00, 0x00, 0x0c,
0x00, 0x03, 0x00, 0x00, 0x00, 0x75, 0x75, 0x31,
0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x13, 0x88,
0x64, 0x64, 0x20, 0x88, 0x88, 0x88, 0x88, 0x88,
0x88, 0x02, 0x88, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};
const long_pkt_result = composeLongPacket(
&pkt_buf, // Packet Buffer
0, // Virtual Channel
MIPI_DSI_DCS_LONG_WRITE, // DCS Command
&long_pkt, // Transmit Buffer
long_pkt.len // Buffer Length
);
debug("Result:", .{});
dump_buffer(&long_pkt_result[0], long_pkt_result.len);
assert( // Verify result
std.mem.eql(
u8,
long_pkt_result,
&[_]u8 {
0x39, 0x40, 0x00, 0x25, 0xe9, 0x82, 0x10, 0x06,
0x05, 0xa2, 0x0a, 0xa5, 0x12, 0x31, 0x23, 0x37,
0x83, 0x04, 0xbc, 0x27, 0x38, 0x0c, 0x00, 0x03,
0x00, 0x00, 0x00, 0x0c, 0x00, 0x03, 0x00, 0x00,
0x00, 0x75, 0x75, 0x31, 0x88, 0x88, 0x88, 0x88,
0x88, 0x88, 0x13, 0x88, 0x64, 0x64, 0x20, 0x88,
0x88, 0x88, 0x88, 0x88, 0x88, 0x02, 0x88, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x65, 0x03,
}
)
);
// Write to MIPI DSI
// _ = nuttx_mipi_dsi_dcs_write(
// null, // Device
// 0, // Virtual Channel
// MIPI_DSI_DCS_LONG_WRITE, // DCS Command
// &long_pkt, // Transmit Buffer
// long_pkt.len // Buffer Length
// );
}
// Test Case for DCS Short Write (Without Parameter):
// mipi_dsi_dcs_write: short len=1
// 11
// .{ 0x0300, 0x36001105 },
// header: 36001105
// .{ 0x0200, 0x00000003 },
// len: 3
// Test Case for DCS Short Write (With Parameter):
// mipi_dsi_dcs_write: short len=2
// bc 4e
// .{ 0x0300, 0x354ebc15 },
// header: 354ebc15
// .{ 0x0200, 0x00000003 },
// len: 3
// Test Case for DCS Long Write:
// mipi_dsi_dcs_write: long len=64
// e9 82 10 06 05 a2 0a a5
// 12 31 23 37 83 04 bc 27
// 38 0c 00 03 00 00 00 0c
// 00 03 00 00 00 75 75 31
// 88 88 88 88 88 88 13 88
// 64 64 20 88 88 88 88 88
// 88 02 88 00 00 00 00 00
// 00 00 00 00 00 00 00 00
// .{ 0x0300, 0x25004039 },
// header: 25004039
// display_zalloc: size=70
// .{ 0x0304, 0x061082e9 },
// .{ 0x0308, 0xa50aa205 },
// .{ 0x030c, 0x37233112 },
// .{ 0x0310, 0x27bc0483 },
// .{ 0x0314, 0x03000c38 },
// .{ 0x0318, 0x0c000000 },
// .{ 0x031c, 0x00000300 },
// .{ 0x0320, 0x31757500 },
// .{ 0x0324, 0x88888888 },
// .{ 0x0328, 0x88138888 },
// .{ 0x032c, 0x88206464 },
// .{ 0x0330, 0x88888888 },
// .{ 0x0334, 0x00880288 },
// .{ 0x0338, 0x00000000 },
// .{ 0x033c, 0x00000000 },
// .{ 0x0340, 0x00000000 },
// .{ 0x0344, 0x00000365 },
// payload[0]: 061082e9
// payload[1]: a50aa205
// payload[2]: 37233112
// payload[3]: 27bc0483
// payload[4]: 03000c38
// payload[5]: 0c000000
// payload[6]: 00000300
// payload[7]: 31757500
// payload[8]: 88888888
// payload[9]: 88138888
// payload[10]: 88206464
// payload[11]: 88888888
// payload[12]: 00880288
// payload[13]: 00000000
// payload[14]: 00000000
// payload[15]: 00000000
// payload[16]: 00000365
// .{ 0x0200, 0x00000045 },
// len: 69
// Expected Result for DCS Long Write:
// packet: len=70
// 39 40 00 25 e9 82 10 06
// 05 a2 0a a5 12 31 23 37
// 83 04 bc 27 38 0c 00 03
// 00 00 00 0c 00 03 00 00
// 00 75 75 31 88 88 88 88
// 88 88 13 88 64 64 20 88
// 88 88 88 88 88 02 88 00
// 00 00 00 00 00 00 00 00
// 00 00 00 00 65 03
// modifyreg32: addr=0x300, val=0x25004039
// modifyreg32: addr=0x304, val=0x061082e9
// modifyreg32: addr=0x308, val=0xa50aa205
// modifyreg32: addr=0x30c, val=0x37233112
// modifyreg32: addr=0x310, val=0x27bc0483
// modifyreg32: addr=0x314, val=0x03000c38
// modifyreg32: addr=0x318, val=0x0c000000
// modifyreg32: addr=0x31c, val=0x00000300
// modifyreg32: addr=0x320, val=0x31757500
// modifyreg32: addr=0x324, val=0x88888888
// modifyreg32: addr=0x328, val=0x88138888
// modifyreg32: addr=0x32c, val=0x88206464
// modifyreg32: addr=0x330, val=0x88888888
// modifyreg32: addr=0x334, val=0x00880288
// modifyreg32: addr=0x338, val=0x00000000
// modifyreg32: addr=0x33c, val=0x00000000
// modifyreg32: addr=0x340, val=0x00000000
// modifyreg32: addr=0x344, val=0x00000365
// modifyreg32: addr=0x200, val=0x00000045
///////////////////////////////////////////////////////////////////////////////
// Panic Handler
/// Called by Zig when it hits a Panic. We print the Panic Message, Stack Trace and halt. See
/// https://andrewkelley.me/post/zig-stack-traces-kernel-panic-bare-bones-os.html
/// https://github.com/ziglang/zig/blob/master/lib/std/builtin.zig#L763-L847
pub fn panic(
message: []const u8,
_stack_trace: ?*std.builtin.StackTrace
) noreturn {
// Print the Panic Message
_ = _stack_trace;
_ = puts("\n!ZIG PANIC!");
_ = puts(@ptrCast([*c]const u8, message));
// Print the Stack Trace
_ = puts("Stack Trace:");
var it = std.debug.StackIterator.init(@returnAddress(), null);
while (it.next()) |return_address| {
_ = printf("%p\n", return_address);
}
// Halt
c.exit(1);
}
///////////////////////////////////////////////////////////////////////////////
// Logging
/// Called by Zig for `std.log.debug`, `std.log.info`, `std.log.err`, ...
/// https://gist.github.com/leecannon/d6f5d7e5af5881c466161270347ce84d
pub fn log(
comptime _message_level: std.log.Level,
comptime _scope: @Type(.EnumLiteral),
comptime format: []const u8,
args: anytype,
) void {
_ = _message_level;
_ = _scope;
// Format the message
var buf: [100]u8 = undefined; // Limit to 100 chars
var slice = std.fmt.bufPrint(&buf, format, args)
catch { _ = puts("*** log error: buf too small"); return; };
// Terminate the formatted message with a null
var buf2: [buf.len + 1 : 0]u8 = undefined;
std.mem.copy(
u8,
buf2[0..slice.len],
slice[0..slice.len]
);
buf2[slice.len] = 0;
// Print the formatted message
_ = puts(&buf2);
}
///////////////////////////////////////////////////////////////////////////////
// Imported Functions and Variables
/// From apps/examples/hello/hello_main.c
extern fn dump_buffer(data: [*c]const u8, len: usize) void;
/// For safety, we import these functions ourselves to enforce Null-Terminated Strings.
/// We changed `[*c]const u8` to `[*:0]const u8`
extern fn printf(format: [*:0]const u8, ...) c_int;
extern fn puts(str: [*:0]const u8) c_int;
/// Aliases for Zig Standard Library
const assert = std.debug.assert;
const debug = std.log.debug;