+ return lsr & UART_LSR_DR;
+}
+
+void
+lpss_uart_enable( boolean_t on_off )
+{
+ unsigned int pmcs_reg;
+
+ if (!lpss_uart_supported) {
+ return;
+ }
+
+ pmcs_reg = ml_phys_read_byte(PCI_UART2 + 0x84);
+ if (on_off == FALSE) {
+ pmcs_reg |= 0x03;
+ lpss_uart_enabled = 0;
+ } else {
+ pmcs_reg &= ~(0x03);
+ }
+
+ ml_phys_write_byte(PCI_UART2 + 0x84, pmcs_reg);
+ pmcs_reg = ml_phys_read_byte(PCI_UART2 + 0x84);
+
+ if (on_off == TRUE) {
+ lpss_uart_re_init();
+ lpss_uart_enabled = 1;
+ }
+}
+
+static void
+lpss_uart_re_init( void )
+{
+ uint32_t register_read;
+
+ MMIO_WRITE(RST, 0x7); /* LPSS UART2 controller out ot reset */
+ register_read = MMIO_READ(RST);
+
+ MMIO_WRITE(LCR, UART_LCR_DLAB); /* Set DLAB bit to enable reading/writing of DLL, DLH */
+ register_read = MMIO_READ(LCR);
+
+ MMIO_WRITE(DLL, 1); /* Divisor Latch Low Register */
+ register_read = MMIO_READ(DLL);
+
+ MMIO_WRITE(DLM, 0); /* Divisor Latch High Register */
+ register_read = MMIO_READ(DLM);
+
+ MMIO_WRITE(FCR, 1); /* Enable FIFO */
+ register_read = MMIO_READ(FCR);
+
+ MMIO_WRITE(LCR, UART_LCR_8BITS); /* Set 8 bits, clear DLAB */
+ register_read = MMIO_READ(LCR);
+
+ MMIO_WRITE(MCR, UART_MCR_RTS); /* Request to send */
+ register_read = MMIO_READ(MCR);
+
+ MMIO_WRITE(CLK, UART_CLK_125M_1); /* 1.25M Clock speed */
+ register_read = MMIO_READ(CLK);
+
+ MMIO_WRITE(CLK, UART_CLK_125M_2); /* 1.25M Clock speed */
+ register_read = MMIO_READ(CLK);
+}
+
+static int
+mmio_uart_rd0( void )
+{
+ return MMIO_READ( RBR );
+}
+
+static struct pe_serial_functions mmio_uart_serial_functions = {
+ .uart_init = mmio_uart_init,
+ .uart_set_baud_rate = mmio_uart_set_baud_rate,
+ .tr0 = mmio_uart_tr0,
+ .td0 = mmio_uart_td0,
+ .rr0 = mmio_uart_rr0,
+ .rd0 = mmio_uart_rd0
+};
+
+// =============================================================================
+// PCIE_MMIO UART
+// =============================================================================
+
+#define PCIE_MMIO_UART_BASE 0xFE410000
+
+#define PCIE_MMIO_WRITE(r, v) ml_phys_write_byte(pcie_mmio_uart_base + PCIE_MMIO_UART_##r, v)
+#define PCIE_MMIO_READ(r) ml_phys_read_byte(pcie_mmio_uart_base + PCIE_MMIO_UART_##r)
+
+enum {
+ PCIE_MMIO_UART_RBR = 0x0, /* receive buffer Register (R) */
+ PCIE_MMIO_UART_THR = 0x0, /* transmit holding register (W) */
+ PCIE_MMIO_UART_IER = 0x1, /* interrupt enable register */
+ PCIE_MMIO_UART_FCR = 0x2, /* fifo control register (W) */
+ PCIE_MMIO_UART_LCR = 0x4, /* line control register */
+ PCIE_MMIO_UART_MCR = 0x4, /* modem control register */
+ PCIE_MMIO_UART_LSR = 0x5, /* line status register */
+ PCIE_MMIO_UART_DLL = 0x8, /* DLAB = 1, divisor latch (LSB) */
+ PCIE_MMIO_UART_DLM = 0x9, /* DLAB = 1, divisor latch (MSB) */
+ PCIE_MMIO_UART_SCR = 0x30, /* scratch register */
+};
+
+static vm_offset_t pcie_mmio_uart_base = 0;
+
+static int
+pcie_mmio_uart_present( void )
+{
+ PCIE_MMIO_WRITE( SCR, 0x5a );
+ if (PCIE_MMIO_READ(SCR) != 0x5a) {
+ return 0;
+ }
+ PCIE_MMIO_WRITE( SCR, 0xa5 );
+ if (PCIE_MMIO_READ(SCR) != 0xa5) {
+ return 0;
+ }
+
+ return 1;
+}
+
+static int
+pcie_mmio_uart_probe( void )
+{
+ unsigned new_pcie_mmio_uart_base = 0;
+
+ // if specified, pcie_mmio_uart overrides all probing
+ if (PE_parse_boot_argn("pcie_mmio_uart", &new_pcie_mmio_uart_base, sizeof(new_pcie_mmio_uart_base))) {
+ // pcie_mmio_uart=0 will disable pcie_mmio_uart support
+ if (new_pcie_mmio_uart_base == 0) {
+ return 0;
+ }
+ pcie_mmio_uart_base = new_pcie_mmio_uart_base;
+ return 1;
+ }
+
+ pcie_mmio_uart_base = PCIE_MMIO_UART_BASE;
+ if (pcie_mmio_uart_present()) {
+ return 1;
+ }
+
+ // no pcie_mmio uart found
+ return 0;
+}
+
+static void
+pcie_mmio_uart_set_baud_rate( __unused int unit, __unused uint32_t baud_rate )
+{
+ const unsigned char lcr = PCIE_MMIO_READ( LCR );
+ unsigned long div;
+
+ if (baud_rate == 0) {
+ baud_rate = 9600;
+ }
+ div = LEGACY_UART_CLOCK / 16 / baud_rate;
+
+ PCIE_MMIO_WRITE( LCR, lcr | UART_LCR_DLAB );
+ PCIE_MMIO_WRITE( DLM, (unsigned char)(div >> 8));
+ PCIE_MMIO_WRITE( DLL, (unsigned char) div );
+ PCIE_MMIO_WRITE( LCR, lcr & ~UART_LCR_DLAB);
+}
+
+static int
+pcie_mmio_uart_tr0( void )
+{
+ return PCIE_MMIO_READ(LSR) & UART_LSR_THRE;
+}
+
+static void
+pcie_mmio_uart_td0( int c )
+{
+ PCIE_MMIO_WRITE( THR, c );
+}
+
+static void
+pcie_mmio_uart_init( void )
+{
+ uart_initted = 1;
+}
+
+static int
+pcie_mmio_uart_rr0( void )
+{
+ unsigned char lsr;
+
+ lsr = PCIE_MMIO_READ( LSR );
+
+ if (lsr & (UART_LSR_FE | UART_LSR_PE | UART_LSR_OE)) {
+ PCIE_MMIO_READ( RBR ); /* discard */
+ return 0;
+ }
+
+ return lsr & UART_LSR_DR;
+}
+
+static int
+pcie_mmio_uart_rd0( void )
+{
+ return PCIE_MMIO_READ( RBR );
+}
+
+static struct pe_serial_functions pcie_mmio_uart_serial_functions = {
+ .uart_init = pcie_mmio_uart_init,
+ .uart_set_baud_rate = pcie_mmio_uart_set_baud_rate,
+ .tr0 = pcie_mmio_uart_tr0,
+ .td0 = pcie_mmio_uart_td0,
+ .rr0 = pcie_mmio_uart_rr0,
+ .rd0 = pcie_mmio_uart_rd0
+};
+
+// =============================================================================
+// Generic serial support below
+// =============================================================================
+
+int
+serial_init( void )
+{
+ unsigned new_uart_baud_rate = 0;
+
+ if (PE_parse_boot_argn("serialbaud", &new_uart_baud_rate, sizeof(new_uart_baud_rate))) {
+ /* Valid divisor? */
+ if (!((LEGACY_UART_CLOCK / 16) % new_uart_baud_rate)) {
+ uart_baud_rate = new_uart_baud_rate;
+ }
+ }
+
+ if (mmio_uart_probe()) {
+ gPESF = &mmio_uart_serial_functions;
+ gPESF->uart_init();
+ lpss_uart_supported = 1;
+ lpss_uart_enabled = 1;
+ return 1;
+ } else if (legacy_uart_probe()) {
+ gPESF = &legacy_uart_serial_functions;
+ gPESF->uart_init();
+ legacy_uart_enabled = 1;
+ return 1;
+ } else if (pcie_mmio_uart_probe()) {
+ gPESF = &pcie_mmio_uart_serial_functions;
+ gPESF->uart_init();
+ pcie_uart_enabled = 1;
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+static void
+uart_putc(char c)
+{
+ if (uart_initted && (legacy_uart_enabled || lpss_uart_enabled || pcie_uart_enabled)) {
+ while (!gPESF->tr0()) {
+ ; /* Wait until THR is empty. */
+ }
+ gPESF->td0(c);
+ }
+}
+
+static int
+uart_getc(void)
+{
+ if (uart_initted && (legacy_uart_enabled || lpss_uart_enabled || pcie_uart_enabled)) {
+ if (!gPESF->rr0()) {
+ return -1;
+ }
+ return gPESF->rd0();
+ }
+ return -1;
projects / apple / xnu.git / blobdiff