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-rw-r--r--plat/nvidia/tegra/drivers/spe/shared_console.S187
1 files changed, 187 insertions, 0 deletions
diff --git a/plat/nvidia/tegra/drivers/spe/shared_console.S b/plat/nvidia/tegra/drivers/spe/shared_console.S
new file mode 100644
index 0000000..d1b18dd
--- /dev/null
+++ b/plat/nvidia/tegra/drivers/spe/shared_console.S
@@ -0,0 +1,187 @@
+/*
+ * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#include <asm_macros.S>
+#include <assert_macros.S>
+#include <console_macros.S>
+
+#define CONSOLE_NUM_BYTES_SHIFT 24
+#define CONSOLE_FLUSH_DATA_TO_PORT (1 << 26)
+#define CONSOLE_RING_DOORBELL (1 << 31)
+#define CONSOLE_IS_BUSY (1 << 31)
+#define CONSOLE_TIMEOUT 0xC000 /* 50 ms */
+
+ /*
+ * This file contains a driver implementation to make use of the
+ * real console implementation provided by the SPE firmware running
+ * SoCs after Tegra186.
+ *
+ * This console is shared by multiple components and the SPE firmware
+ * finally displays everything on the UART port.
+ */
+
+ .globl console_spe_core_init
+ .globl console_spe_core_putc
+ .globl console_spe_core_getc
+ .globl console_spe_core_flush
+ .globl console_spe_putc
+ .globl console_spe_getc
+ .globl console_spe_flush
+ .globl console_spe_register
+
+.macro check_if_console_is_ready base, tmp1, tmp2, label
+ /* wait until spe is ready or timeout expires */
+ mrs \tmp2, cntps_tval_el1
+1: ldr \tmp1, [\base]
+ and \tmp1, \tmp1, #CONSOLE_IS_BUSY
+ cbz \tmp1, 2f
+ mrs \tmp1, cntps_tval_el1
+ sub \tmp1, \tmp2, \tmp1
+ cmp \tmp1, #CONSOLE_TIMEOUT
+ b.lt 1b
+ b \label
+2:
+.endm
+
+ /* -------------------------------------------------
+ * int console_spe_register(uintptr_t baseaddr,
+ * uint32_t clock, uint32_t baud,
+ * console_t *console);
+ * Function to initialize and register a new spe
+ * console. Storage passed in for the console struct
+ * *must* be persistent (i.e. not from the stack).
+ * In: x0 - UART register base address
+ * w1 - UART clock in Hz
+ * w2 - Baud rate
+ * x3 - pointer to empty console_t struct
+ * Out: return 1 on success, 0 on error
+ * Clobber list : x0, x1, x2, x6, x7, x14
+ * -------------------------------------------------
+ */
+func console_spe_register
+ /* Check the input base address */
+ cbz x0, register_fail
+
+ /* Dont use clock or baud rate, so ok to overwrite them */
+ check_if_console_is_ready x0, x1, x2, register_fail
+
+ cbz x3, register_fail
+ str x0, [x3, #CONSOLE_T_BASE]
+ mov x0, x3
+ finish_console_register spe putc=1, getc=1, flush=1
+
+register_fail:
+ mov w0, wzr
+ ret
+endfunc console_spe_register
+
+ /* --------------------------------------------------------
+ * int console_spe_core_putc(int c, uintptr_t base_addr)
+ * Function to output a character over the console. It
+ * returns the character printed on success or -1 on error.
+ * In : w0 - character to be printed
+ * x1 - console base address
+ * Out : return -1 on error else return character.
+ * Clobber list : x2, x3
+ * --------------------------------------------------------
+ */
+func console_spe_core_putc
+ /* Check the input parameter */
+ cbz x1, putc_error
+
+ /* Prepend '\r' to '\n' */
+ cmp w0, #0xA
+ b.ne not_eol
+
+ check_if_console_is_ready x1, x2, x3, putc_error
+
+ /* spe is ready */
+ mov w2, #0xD /* '\r' */
+ and w2, w2, #0xFF
+ mov w3, #(CONSOLE_RING_DOORBELL | (1 << CONSOLE_NUM_BYTES_SHIFT))
+ orr w2, w2, w3
+ str w2, [x1]
+
+not_eol:
+ check_if_console_is_ready x1, x2, x3, putc_error
+
+ /* spe is ready */
+ mov w2, w0
+ and w2, w2, #0xFF
+ mov w3, #(CONSOLE_RING_DOORBELL | (1 << CONSOLE_NUM_BYTES_SHIFT))
+ orr w2, w2, w3
+ str w2, [x1]
+
+ ret
+putc_error:
+ mov w0, #-1
+ ret
+endfunc console_spe_core_putc
+
+ /* --------------------------------------------------------
+ * int console_spe_putc(int c, console_t *console)
+ * Function to output a character over the console. It
+ * returns the character printed on success or -1 on error.
+ * In : w0 - character to be printed
+ * x1 - pointer to console_t structure
+ * Out : return -1 on error else return character.
+ * Clobber list : x2
+ * --------------------------------------------------------
+ */
+func console_spe_putc
+ ldr x1, [x1, #CONSOLE_T_BASE]
+ b console_spe_core_putc
+endfunc console_spe_putc
+
+ /* ---------------------------------------------
+ * int console_spe_getc(console_t *console)
+ * Function to get a character from the console.
+ * It returns the character grabbed on success
+ * or -1 if no character is available.
+ * In : x0 - pointer to console_t structure
+ * Out: w0 - character if available, else -1
+ * Clobber list : x0, x1
+ * ---------------------------------------------
+ */
+func console_spe_getc
+ mov w0, #-1
+ ret
+endfunc console_spe_getc
+
+ /* -------------------------------------------------
+ * void console_spe_core_flush(uintptr_t base_addr)
+ * Function to force a write of all buffered
+ * data that hasn't been output.
+ * In : x0 - console base address
+ * Out : void.
+ * Clobber list : x0, x1
+ * -------------------------------------------------
+ */
+func console_spe_core_flush
+#if ENABLE_ASSERTIONS
+ cmp x0, #0
+ ASM_ASSERT(ne)
+#endif /* ENABLE_ASSERTIONS */
+
+ /* flush console */
+ mov w1, #(CONSOLE_RING_DOORBELL | CONSOLE_FLUSH_DATA_TO_PORT)
+ str w1, [x0]
+ ret
+endfunc console_spe_core_flush
+
+ /* ---------------------------------------------
+ * void console_spe_flush(console_t *console)
+ * Function to force a write of all buffered
+ * data that hasn't been output.
+ * In : x0 - pointer to console_t structure
+ * Out : void.
+ * Clobber list : x0, x1
+ * ---------------------------------------------
+ */
+func console_spe_flush
+ ldr x0, [x0, #CONSOLE_T_BASE]
+ b console_spe_core_flush
+endfunc console_spe_flush