From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- arch/arm/mach-imx/ssi-fiq.S | 144 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 arch/arm/mach-imx/ssi-fiq.S (limited to 'arch/arm/mach-imx/ssi-fiq.S') diff --git a/arch/arm/mach-imx/ssi-fiq.S b/arch/arm/mach-imx/ssi-fiq.S new file mode 100644 index 000000000..68d7fdea9 --- /dev/null +++ b/arch/arm/mach-imx/ssi-fiq.S @@ -0,0 +1,144 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2009 Sascha Hauer + */ + +#include +#include + +/* + * r8 = bit 0-15: tx offset, bit 16-31: tx buffer size + * r9 = bit 0-15: rx offset, bit 16-31: rx buffer size + */ + +#define SSI_STX0 0x00 +#define SSI_SRX0 0x08 +#define SSI_SISR 0x14 +#define SSI_SIER 0x18 +#define SSI_SACNT 0x38 + +#define SSI_SACNT_AC97EN (1 << 0) + +#define SSI_SIER_TFE0_EN (1 << 0) +#define SSI_SISR_TFE0 (1 << 0) +#define SSI_SISR_RFF0 (1 << 2) +#define SSI_SIER_RFF0_EN (1 << 2) + + .text + .global imx_ssi_fiq_start + .global imx_ssi_fiq_end + .global imx_ssi_fiq_base + .global imx_ssi_fiq_rx_buffer + .global imx_ssi_fiq_tx_buffer + +/* + * imx_ssi_fiq_start is _intentionally_ not marked as a function symbol + * using ENDPROC(). imx_ssi_fiq_start and imx_ssi_fiq_end are used to + * mark the function body so that it can be copied to the FIQ vector in + * the vectors page. imx_ssi_fiq_start should only be called as the result + * of an FIQ: calling it directly will not work. + */ +imx_ssi_fiq_start: + ldr r12, .L_imx_ssi_fiq_base + + /* TX */ + ldr r13, .L_imx_ssi_fiq_tx_buffer + + /* shall we send? */ + ldr r11, [r12, #SSI_SIER] + tst r11, #SSI_SIER_TFE0_EN + beq 1f + + /* TX FIFO empty? */ + ldr r11, [r12, #SSI_SISR] + tst r11, #SSI_SISR_TFE0 + beq 1f + + mov r10, #0x10000 + sub r10, #1 + and r10, r10, r8 /* r10: current buffer offset */ + + add r13, r13, r10 + + ldrh r11, [r13] + strh r11, [r12, #SSI_STX0] + + ldrh r11, [r13, #2] + strh r11, [r12, #SSI_STX0] + + ldrh r11, [r13, #4] + strh r11, [r12, #SSI_STX0] + + ldrh r11, [r13, #6] + strh r11, [r12, #SSI_STX0] + + add r10, #8 + lsr r11, r8, #16 /* r11: buffer size */ + cmp r10, r11 + lslgt r8, r11, #16 + addle r8, #8 +1: + /* RX */ + + /* shall we receive? */ + ldr r11, [r12, #SSI_SIER] + tst r11, #SSI_SIER_RFF0_EN + beq 1f + + /* RX FIFO full? */ + ldr r11, [r12, #SSI_SISR] + tst r11, #SSI_SISR_RFF0 + beq 1f + + ldr r13, .L_imx_ssi_fiq_rx_buffer + + mov r10, #0x10000 + sub r10, #1 + and r10, r10, r9 /* r10: current buffer offset */ + + add r13, r13, r10 + + ldr r11, [r12, #SSI_SACNT] + tst r11, #SSI_SACNT_AC97EN + + ldr r11, [r12, #SSI_SRX0] + strh r11, [r13] + + ldr r11, [r12, #SSI_SRX0] + strh r11, [r13, #2] + + /* dummy read to skip slot 12 */ + ldrne r11, [r12, #SSI_SRX0] + + ldr r11, [r12, #SSI_SRX0] + strh r11, [r13, #4] + + ldr r11, [r12, #SSI_SRX0] + strh r11, [r13, #6] + + /* dummy read to skip slot 12 */ + ldrne r11, [r12, #SSI_SRX0] + + add r10, #8 + lsr r11, r9, #16 /* r11: buffer size */ + cmp r10, r11 + lslgt r9, r11, #16 + addle r9, #8 + +1: + @ return from FIQ + subs pc, lr, #4 + + .align +.L_imx_ssi_fiq_base: +imx_ssi_fiq_base: + .word 0x0 +.L_imx_ssi_fiq_rx_buffer: +imx_ssi_fiq_rx_buffer: + .word 0x0 +.L_imx_ssi_fiq_tx_buffer: +imx_ssi_fiq_tx_buffer: + .word 0x0 +.L_imx_ssi_fiq_end: +imx_ssi_fiq_end: + -- cgit v1.2.3