Files
linux-stable-mirror/drivers/video/fbdev/omap/lcd_dma.c
Aaro Koskinen aa8e22cbed fbdev: omap: use threaded IRQ for LCD DMA
[ Upstream commit e4b6b665df ]

When using touchscreen and framebuffer, Nokia 770 crashes easily with:

    BUG: scheduling while atomic: irq/144-ads7846/82/0x00010000
    Modules linked in: usb_f_ecm g_ether usb_f_rndis u_ether libcomposite configfs omap_udc ohci_omap ohci_hcd
    CPU: 0 UID: 0 PID: 82 Comm: irq/144-ads7846 Not tainted 6.12.7-770 #2
    Hardware name: Nokia 770
    Call trace:
     unwind_backtrace from show_stack+0x10/0x14
     show_stack from dump_stack_lvl+0x54/0x5c
     dump_stack_lvl from __schedule_bug+0x50/0x70
     __schedule_bug from __schedule+0x4d4/0x5bc
     __schedule from schedule+0x34/0xa0
     schedule from schedule_preempt_disabled+0xc/0x10
     schedule_preempt_disabled from __mutex_lock.constprop.0+0x218/0x3b4
     __mutex_lock.constprop.0 from clk_prepare_lock+0x38/0xe4
     clk_prepare_lock from clk_set_rate+0x18/0x154
     clk_set_rate from sossi_read_data+0x4c/0x168
     sossi_read_data from hwa742_read_reg+0x5c/0x8c
     hwa742_read_reg from send_frame_handler+0xfc/0x300
     send_frame_handler from process_pending_requests+0x74/0xd0
     process_pending_requests from lcd_dma_irq_handler+0x50/0x74
     lcd_dma_irq_handler from __handle_irq_event_percpu+0x44/0x130
     __handle_irq_event_percpu from handle_irq_event+0x28/0x68
     handle_irq_event from handle_level_irq+0x9c/0x170
     handle_level_irq from generic_handle_domain_irq+0x2c/0x3c
     generic_handle_domain_irq from omap1_handle_irq+0x40/0x8c
     omap1_handle_irq from generic_handle_arch_irq+0x28/0x3c
     generic_handle_arch_irq from call_with_stack+0x1c/0x24
     call_with_stack from __irq_svc+0x94/0xa8
    Exception stack(0xc5255da0 to 0xc5255de8)
    5da0: 00000001 c22fc620 00000000 00000000 c08384a8 c106fc00 00000000 c240c248
    5dc0: c113a600 c3f6ec30 00000001 00000000 c22fc620 c5255df0 c22fc620 c0279a94
    5de0: 60000013 ffffffff
     __irq_svc from clk_prepare_lock+0x4c/0xe4
     clk_prepare_lock from clk_get_rate+0x10/0x74
     clk_get_rate from uwire_setup_transfer+0x40/0x180
     uwire_setup_transfer from spi_bitbang_transfer_one+0x2c/0x9c
     spi_bitbang_transfer_one from spi_transfer_one_message+0x2d0/0x664
     spi_transfer_one_message from __spi_pump_transfer_message+0x29c/0x498
     __spi_pump_transfer_message from __spi_sync+0x1f8/0x2e8
     __spi_sync from spi_sync+0x24/0x40
     spi_sync from ads7846_halfd_read_state+0x5c/0x1c0
     ads7846_halfd_read_state from ads7846_irq+0x58/0x348
     ads7846_irq from irq_thread_fn+0x1c/0x78
     irq_thread_fn from irq_thread+0x120/0x228
     irq_thread from kthread+0xc8/0xe8
     kthread from ret_from_fork+0x14/0x28

As a quick fix, switch to a threaded IRQ which provides a stable system.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:22 +01:00

445 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/mach-omap1/lcd_dma.c
*
* Extracted from arch/arm/plat-omap/dma.c
* Copyright (C) 2003 - 2008 Nokia Corporation
* Author: Juha Yrjölä <juha.yrjola@nokia.com>
* DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
* Graphics DMA and LCD DMA graphics tranformations
* by Imre Deak <imre.deak@nokia.com>
* OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
* Merged to support both OMAP1 and OMAP2 by Tony Lindgren <tony@atomide.com>
* Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* Support functions for the OMAP internal DMA channels.
*/
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/omap-dma.h>
#include <linux/soc/ti/omap1-soc.h>
#include <linux/soc/ti/omap1-io.h>
#include "lcdc.h"
#include "lcd_dma.h"
int omap_lcd_dma_running(void)
{
/*
* On OMAP1510, internal LCD controller will start the transfer
* when it gets enabled, so assume DMA running if LCD enabled.
*/
if (cpu_is_omap15xx())
if (omap_readw(OMAP_LCDC_CONTROL) & OMAP_LCDC_CTRL_LCD_EN)
return 1;
/* Check if LCD DMA is running */
if (cpu_is_omap16xx())
if (omap_readw(OMAP1610_DMA_LCD_CCR) & OMAP_DMA_CCR_EN)
return 1;
return 0;
}
static struct lcd_dma_info {
spinlock_t lock;
int reserved;
void (*callback)(u16 status, void *data);
void *cb_data;
int active;
unsigned long addr;
int rotate, data_type, xres, yres;
int vxres;
int mirror;
int xscale, yscale;
int ext_ctrl;
int src_port;
int single_transfer;
} lcd_dma;
void omap_set_lcd_dma_b1(unsigned long addr, u16 fb_xres, u16 fb_yres,
int data_type)
{
lcd_dma.addr = addr;
lcd_dma.data_type = data_type;
lcd_dma.xres = fb_xres;
lcd_dma.yres = fb_yres;
}
EXPORT_SYMBOL(omap_set_lcd_dma_b1);
void omap_set_lcd_dma_ext_controller(int external)
{
lcd_dma.ext_ctrl = external;
}
EXPORT_SYMBOL(omap_set_lcd_dma_ext_controller);
void omap_set_lcd_dma_single_transfer(int single)
{
lcd_dma.single_transfer = single;
}
EXPORT_SYMBOL(omap_set_lcd_dma_single_transfer);
void omap_set_lcd_dma_b1_rotation(int rotate)
{
if (cpu_is_omap15xx()) {
printk(KERN_ERR "DMA rotation is not supported in 1510 mode\n");
BUG();
return;
}
lcd_dma.rotate = rotate;
}
EXPORT_SYMBOL(omap_set_lcd_dma_b1_rotation);
void omap_set_lcd_dma_b1_mirror(int mirror)
{
if (cpu_is_omap15xx()) {
printk(KERN_ERR "DMA mirror is not supported in 1510 mode\n");
BUG();
}
lcd_dma.mirror = mirror;
}
EXPORT_SYMBOL(omap_set_lcd_dma_b1_mirror);
void omap_set_lcd_dma_b1_vxres(unsigned long vxres)
{
if (cpu_is_omap15xx()) {
pr_err("DMA virtual resolution is not supported in 1510 mode\n");
BUG();
}
lcd_dma.vxres = vxres;
}
EXPORT_SYMBOL(omap_set_lcd_dma_b1_vxres);
void omap_set_lcd_dma_b1_scale(unsigned int xscale, unsigned int yscale)
{
if (cpu_is_omap15xx()) {
printk(KERN_ERR "DMA scale is not supported in 1510 mode\n");
BUG();
}
lcd_dma.xscale = xscale;
lcd_dma.yscale = yscale;
}
EXPORT_SYMBOL(omap_set_lcd_dma_b1_scale);
static void set_b1_regs(void)
{
unsigned long top, bottom;
int es;
u16 w;
unsigned long en, fn;
long ei, fi;
unsigned long vxres;
unsigned int xscale, yscale;
switch (lcd_dma.data_type) {
case OMAP_DMA_DATA_TYPE_S8:
es = 1;
break;
case OMAP_DMA_DATA_TYPE_S16:
es = 2;
break;
case OMAP_DMA_DATA_TYPE_S32:
es = 4;
break;
default:
BUG();
return;
}
vxres = lcd_dma.vxres ? lcd_dma.vxres : lcd_dma.xres;
xscale = lcd_dma.xscale ? lcd_dma.xscale : 1;
yscale = lcd_dma.yscale ? lcd_dma.yscale : 1;
BUG_ON(vxres < lcd_dma.xres);
#define PIXADDR(x, y) (lcd_dma.addr + \
((y) * vxres * yscale + (x) * xscale) * es)
#define PIXSTEP(sx, sy, dx, dy) (PIXADDR(dx, dy) - PIXADDR(sx, sy) - es + 1)
switch (lcd_dma.rotate) {
case 0:
if (!lcd_dma.mirror) {
top = PIXADDR(0, 0);
bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
/* 1510 DMA requires the bottom address to be 2 more
* than the actual last memory access location. */
if (cpu_is_omap15xx() &&
lcd_dma.data_type == OMAP_DMA_DATA_TYPE_S32)
bottom += 2;
ei = PIXSTEP(0, 0, 1, 0);
fi = PIXSTEP(lcd_dma.xres - 1, 0, 0, 1);
} else {
top = PIXADDR(lcd_dma.xres - 1, 0);
bottom = PIXADDR(0, lcd_dma.yres - 1);
ei = PIXSTEP(1, 0, 0, 0);
fi = PIXSTEP(0, 0, lcd_dma.xres - 1, 1);
}
en = lcd_dma.xres;
fn = lcd_dma.yres;
break;
case 90:
if (!lcd_dma.mirror) {
top = PIXADDR(0, lcd_dma.yres - 1);
bottom = PIXADDR(lcd_dma.xres - 1, 0);
ei = PIXSTEP(0, 1, 0, 0);
fi = PIXSTEP(0, 0, 1, lcd_dma.yres - 1);
} else {
top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
bottom = PIXADDR(0, 0);
ei = PIXSTEP(0, 1, 0, 0);
fi = PIXSTEP(1, 0, 0, lcd_dma.yres - 1);
}
en = lcd_dma.yres;
fn = lcd_dma.xres;
break;
case 180:
if (!lcd_dma.mirror) {
top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
bottom = PIXADDR(0, 0);
ei = PIXSTEP(1, 0, 0, 0);
fi = PIXSTEP(0, 1, lcd_dma.xres - 1, 0);
} else {
top = PIXADDR(0, lcd_dma.yres - 1);
bottom = PIXADDR(lcd_dma.xres - 1, 0);
ei = PIXSTEP(0, 0, 1, 0);
fi = PIXSTEP(lcd_dma.xres - 1, 1, 0, 0);
}
en = lcd_dma.xres;
fn = lcd_dma.yres;
break;
case 270:
if (!lcd_dma.mirror) {
top = PIXADDR(lcd_dma.xres - 1, 0);
bottom = PIXADDR(0, lcd_dma.yres - 1);
ei = PIXSTEP(0, 0, 0, 1);
fi = PIXSTEP(1, lcd_dma.yres - 1, 0, 0);
} else {
top = PIXADDR(0, 0);
bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
ei = PIXSTEP(0, 0, 0, 1);
fi = PIXSTEP(0, lcd_dma.yres - 1, 1, 0);
}
en = lcd_dma.yres;
fn = lcd_dma.xres;
break;
default:
BUG();
return; /* Suppress warning about uninitialized vars */
}
if (cpu_is_omap15xx()) {
omap_writew(top >> 16, OMAP1510_DMA_LCD_TOP_F1_U);
omap_writew(top, OMAP1510_DMA_LCD_TOP_F1_L);
omap_writew(bottom >> 16, OMAP1510_DMA_LCD_BOT_F1_U);
omap_writew(bottom, OMAP1510_DMA_LCD_BOT_F1_L);
return;
}
/* 1610 regs */
omap_writew(top >> 16, OMAP1610_DMA_LCD_TOP_B1_U);
omap_writew(top, OMAP1610_DMA_LCD_TOP_B1_L);
omap_writew(bottom >> 16, OMAP1610_DMA_LCD_BOT_B1_U);
omap_writew(bottom, OMAP1610_DMA_LCD_BOT_B1_L);
omap_writew(en, OMAP1610_DMA_LCD_SRC_EN_B1);
omap_writew(fn, OMAP1610_DMA_LCD_SRC_FN_B1);
w = omap_readw(OMAP1610_DMA_LCD_CSDP);
w &= ~0x03;
w |= lcd_dma.data_type;
omap_writew(w, OMAP1610_DMA_LCD_CSDP);
w = omap_readw(OMAP1610_DMA_LCD_CTRL);
/* Always set the source port as SDRAM for now*/
w &= ~(0x03 << 6);
if (lcd_dma.callback != NULL)
w |= 1 << 1; /* Block interrupt enable */
else
w &= ~(1 << 1);
omap_writew(w, OMAP1610_DMA_LCD_CTRL);
if (!(lcd_dma.rotate || lcd_dma.mirror ||
lcd_dma.vxres || lcd_dma.xscale || lcd_dma.yscale))
return;
w = omap_readw(OMAP1610_DMA_LCD_CCR);
/* Set the double-indexed addressing mode */
w |= (0x03 << 12);
omap_writew(w, OMAP1610_DMA_LCD_CCR);
omap_writew(ei, OMAP1610_DMA_LCD_SRC_EI_B1);
omap_writew(fi >> 16, OMAP1610_DMA_LCD_SRC_FI_B1_U);
omap_writew(fi, OMAP1610_DMA_LCD_SRC_FI_B1_L);
}
static irqreturn_t lcd_dma_irq_handler(int irq, void *dev_id)
{
u16 w;
w = omap_readw(OMAP1610_DMA_LCD_CTRL);
if (unlikely(!(w & (1 << 3)))) {
printk(KERN_WARNING "Spurious LCD DMA IRQ\n");
return IRQ_NONE;
}
/* Ack the IRQ */
w |= (1 << 3);
omap_writew(w, OMAP1610_DMA_LCD_CTRL);
lcd_dma.active = 0;
if (lcd_dma.callback != NULL)
lcd_dma.callback(w, lcd_dma.cb_data);
return IRQ_HANDLED;
}
int omap_request_lcd_dma(void (*callback)(u16 status, void *data),
void *data)
{
spin_lock_irq(&lcd_dma.lock);
if (lcd_dma.reserved) {
spin_unlock_irq(&lcd_dma.lock);
printk(KERN_ERR "LCD DMA channel already reserved\n");
BUG();
return -EBUSY;
}
lcd_dma.reserved = 1;
spin_unlock_irq(&lcd_dma.lock);
lcd_dma.callback = callback;
lcd_dma.cb_data = data;
lcd_dma.active = 0;
lcd_dma.single_transfer = 0;
lcd_dma.rotate = 0;
lcd_dma.vxres = 0;
lcd_dma.mirror = 0;
lcd_dma.xscale = 0;
lcd_dma.yscale = 0;
lcd_dma.ext_ctrl = 0;
lcd_dma.src_port = 0;
return 0;
}
EXPORT_SYMBOL(omap_request_lcd_dma);
void omap_free_lcd_dma(void)
{
spin_lock(&lcd_dma.lock);
if (!lcd_dma.reserved) {
spin_unlock(&lcd_dma.lock);
printk(KERN_ERR "LCD DMA is not reserved\n");
BUG();
return;
}
if (!cpu_is_omap15xx())
omap_writew(omap_readw(OMAP1610_DMA_LCD_CCR) & ~1,
OMAP1610_DMA_LCD_CCR);
lcd_dma.reserved = 0;
spin_unlock(&lcd_dma.lock);
}
EXPORT_SYMBOL(omap_free_lcd_dma);
void omap_enable_lcd_dma(void)
{
u16 w;
/*
* Set the Enable bit only if an external controller is
* connected. Otherwise the OMAP internal controller will
* start the transfer when it gets enabled.
*/
if (cpu_is_omap15xx() || !lcd_dma.ext_ctrl)
return;
w = omap_readw(OMAP1610_DMA_LCD_CTRL);
w |= 1 << 8;
omap_writew(w, OMAP1610_DMA_LCD_CTRL);
lcd_dma.active = 1;
w = omap_readw(OMAP1610_DMA_LCD_CCR);
w |= 1 << 7;
omap_writew(w, OMAP1610_DMA_LCD_CCR);
}
EXPORT_SYMBOL(omap_enable_lcd_dma);
void omap_setup_lcd_dma(void)
{
BUG_ON(lcd_dma.active);
if (!cpu_is_omap15xx()) {
/* Set some reasonable defaults */
omap_writew(0x5440, OMAP1610_DMA_LCD_CCR);
omap_writew(0x9102, OMAP1610_DMA_LCD_CSDP);
omap_writew(0x0004, OMAP1610_DMA_LCD_LCH_CTRL);
}
set_b1_regs();
if (!cpu_is_omap15xx()) {
u16 w;
w = omap_readw(OMAP1610_DMA_LCD_CCR);
/*
* If DMA was already active set the end_prog bit to have
* the programmed register set loaded into the active
* register set.
*/
w |= 1 << 11; /* End_prog */
if (!lcd_dma.single_transfer)
w |= (3 << 8); /* Auto_init, repeat */
omap_writew(w, OMAP1610_DMA_LCD_CCR);
}
}
EXPORT_SYMBOL(omap_setup_lcd_dma);
void omap_stop_lcd_dma(void)
{
u16 w;
lcd_dma.active = 0;
if (cpu_is_omap15xx() || !lcd_dma.ext_ctrl)
return;
w = omap_readw(OMAP1610_DMA_LCD_CCR);
w &= ~(1 << 7);
omap_writew(w, OMAP1610_DMA_LCD_CCR);
w = omap_readw(OMAP1610_DMA_LCD_CTRL);
w &= ~(1 << 8);
omap_writew(w, OMAP1610_DMA_LCD_CTRL);
}
EXPORT_SYMBOL(omap_stop_lcd_dma);
static int __init omap_init_lcd_dma(void)
{
int r;
if (!cpu_class_is_omap1())
return -ENODEV;
if (cpu_is_omap16xx()) {
u16 w;
/* this would prevent OMAP sleep */
w = omap_readw(OMAP1610_DMA_LCD_CTRL);
w &= ~(1 << 8);
omap_writew(w, OMAP1610_DMA_LCD_CTRL);
}
spin_lock_init(&lcd_dma.lock);
r = request_threaded_irq(INT_DMA_LCD, NULL, lcd_dma_irq_handler,
IRQF_ONESHOT, "LCD DMA", NULL);
if (r != 0)
pr_err("unable to request IRQ for LCD DMA (error %d)\n", r);
return r;
}
arch_initcall(omap_init_lcd_dma);