ARM: OMAP: Fix McBSP spin_lock deadlock

A spin_lock deadlock will occur when omap_mcbsp_request() is invoked.

omap_mcbsp_request()
\- clk_enable(mcbsp->clk)         [takes and holds clockfw_lock]
    \- omap2_clk_enable()
       \- _omap2_clk_enable()
           \- omap_mcbsp_clk_enable()
              \- clk_enable(child clock)   [tries for clockfw_lock again]

mcbsp_clk is a virtual clock and it comprises several child clocks. when
enable mcbsp_clk in omap_mcbsp_request(), the enable function of mcbsp_clk
will enable its child clocks, then the deadlock occurs.

The solution is to remove the virtual clock and enable these child clocks in
omap_mcbsp_request() directly.

Signed-off-by: Stanley.Miao <stanley.miao@windriver.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
This commit is contained in:
Stanley.Miao 2009-01-29 08:57:12 -08:00 committed by Tony Lindgren
parent 18e352e4a7
commit 06151158f2
4 changed files with 78 additions and 223 deletions

View File

@ -28,81 +28,8 @@
#define DPS_RSTCT2_PER_EN (1 << 0)
#define DSP_RSTCT2_WD_PER_EN (1 << 1)
struct mcbsp_internal_clk {
struct clk clk;
struct clk **childs;
int n_childs;
};
#if defined(CONFIG_ARCH_OMAP15XX) || defined(CONFIG_ARCH_OMAP16XX)
static void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk)
{
const char *clk_names[] = { "dsp_ck", "api_ck", "dspxor_ck" };
int i;
mclk->n_childs = ARRAY_SIZE(clk_names);
mclk->childs = kzalloc(mclk->n_childs * sizeof(struct clk *),
GFP_KERNEL);
for (i = 0; i < mclk->n_childs; i++) {
/* We fake a platform device to get correct device id */
struct platform_device pdev;
pdev.dev.bus = &platform_bus_type;
pdev.id = mclk->clk.id;
mclk->childs[i] = clk_get(&pdev.dev, clk_names[i]);
if (IS_ERR(mclk->childs[i]))
printk(KERN_ERR "Could not get clock %s (%d).\n",
clk_names[i], mclk->clk.id);
}
}
static int omap_mcbsp_clk_enable(struct clk *clk)
{
struct mcbsp_internal_clk *mclk = container_of(clk,
struct mcbsp_internal_clk, clk);
int i;
for (i = 0; i < mclk->n_childs; i++)
clk_enable(mclk->childs[i]);
return 0;
}
static void omap_mcbsp_clk_disable(struct clk *clk)
{
struct mcbsp_internal_clk *mclk = container_of(clk,
struct mcbsp_internal_clk, clk);
int i;
for (i = 0; i < mclk->n_childs; i++)
clk_disable(mclk->childs[i]);
}
static struct mcbsp_internal_clk omap_mcbsp_clks[] = {
{
.clk = {
.name = "mcbsp_clk",
.id = 1,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
{
.clk = {
.name = "mcbsp_clk",
.id = 3,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
};
#define omap_mcbsp_clks_size ARRAY_SIZE(omap_mcbsp_clks)
#else
#define omap_mcbsp_clks_size 0
static struct mcbsp_internal_clk __initdata *omap_mcbsp_clks;
static inline void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk)
{ }
const char *clk_names[] = { "dsp_ck", "api_ck", "dspxor_ck" };
#endif
static void omap1_mcbsp_request(unsigned int id)
@ -167,8 +94,9 @@ static struct omap_mcbsp_platform_data omap15xx_mcbsp_pdata[] = {
.rx_irq = INT_McBSP1RX,
.tx_irq = INT_McBSP1TX,
.ops = &omap1_mcbsp_ops,
.clk_name = "mcbsp_clk",
},
.clk_names = clk_names,
.num_clks = 3,
},
{
.phys_base = OMAP1510_MCBSP2_BASE,
.dma_rx_sync = OMAP_DMA_MCBSP2_RX,
@ -184,7 +112,8 @@ static struct omap_mcbsp_platform_data omap15xx_mcbsp_pdata[] = {
.rx_irq = INT_McBSP3RX,
.tx_irq = INT_McBSP3TX,
.ops = &omap1_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 3,
},
};
#define OMAP15XX_MCBSP_PDATA_SZ ARRAY_SIZE(omap15xx_mcbsp_pdata)
@ -202,7 +131,8 @@ static struct omap_mcbsp_platform_data omap16xx_mcbsp_pdata[] = {
.rx_irq = INT_McBSP1RX,
.tx_irq = INT_McBSP1TX,
.ops = &omap1_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 3,
},
{
.phys_base = OMAP1610_MCBSP2_BASE,
@ -219,7 +149,8 @@ static struct omap_mcbsp_platform_data omap16xx_mcbsp_pdata[] = {
.rx_irq = INT_McBSP3RX,
.tx_irq = INT_McBSP3TX,
.ops = &omap1_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 3,
},
};
#define OMAP16XX_MCBSP_PDATA_SZ ARRAY_SIZE(omap16xx_mcbsp_pdata)
@ -230,15 +161,6 @@ static struct omap_mcbsp_platform_data omap16xx_mcbsp_pdata[] = {
int __init omap1_mcbsp_init(void)
{
int i;
for (i = 0; i < omap_mcbsp_clks_size; i++) {
if (cpu_is_omap15xx() || cpu_is_omap16xx()) {
omap_mcbsp_clk_init(&omap_mcbsp_clks[i]);
clk_register(&omap_mcbsp_clks[i].clk);
}
}
if (cpu_is_omap730())
omap_mcbsp_count = OMAP730_MCBSP_PDATA_SZ;
if (cpu_is_omap15xx())

View File

@ -24,106 +24,7 @@
#include <mach/cpu.h>
#include <mach/mcbsp.h>
struct mcbsp_internal_clk {
struct clk clk;
struct clk **childs;
int n_childs;
};
#if defined(CONFIG_ARCH_OMAP24XX) || defined(CONFIG_ARCH_OMAP34XX)
static void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk)
{
const char *clk_names[] = { "mcbsp_ick", "mcbsp_fck" };
int i;
mclk->n_childs = ARRAY_SIZE(clk_names);
mclk->childs = kzalloc(mclk->n_childs * sizeof(struct clk *),
GFP_KERNEL);
for (i = 0; i < mclk->n_childs; i++) {
/* We fake a platform device to get correct device id */
struct platform_device pdev;
pdev.dev.bus = &platform_bus_type;
pdev.id = mclk->clk.id;
mclk->childs[i] = clk_get(&pdev.dev, clk_names[i]);
if (IS_ERR(mclk->childs[i]))
printk(KERN_ERR "Could not get clock %s (%d).\n",
clk_names[i], mclk->clk.id);
}
}
static int omap_mcbsp_clk_enable(struct clk *clk)
{
struct mcbsp_internal_clk *mclk = container_of(clk,
struct mcbsp_internal_clk, clk);
int i;
for (i = 0; i < mclk->n_childs; i++)
clk_enable(mclk->childs[i]);
return 0;
}
static void omap_mcbsp_clk_disable(struct clk *clk)
{
struct mcbsp_internal_clk *mclk = container_of(clk,
struct mcbsp_internal_clk, clk);
int i;
for (i = 0; i < mclk->n_childs; i++)
clk_disable(mclk->childs[i]);
}
static struct mcbsp_internal_clk omap_mcbsp_clks[] = {
{
.clk = {
.name = "mcbsp_clk",
.id = 1,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
{
.clk = {
.name = "mcbsp_clk",
.id = 2,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
{
.clk = {
.name = "mcbsp_clk",
.id = 3,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
{
.clk = {
.name = "mcbsp_clk",
.id = 4,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
{
.clk = {
.name = "mcbsp_clk",
.id = 5,
.enable = omap_mcbsp_clk_enable,
.disable = omap_mcbsp_clk_disable,
},
},
};
#define omap_mcbsp_clks_size ARRAY_SIZE(omap_mcbsp_clks)
#else
#define omap_mcbsp_clks_size 0
static struct mcbsp_internal_clk __initdata *omap_mcbsp_clks;
static inline void omap_mcbsp_clk_init(struct clk *clk)
{ }
#endif
const char *clk_names[] = { "mcbsp_ick", "mcbsp_fck" };
static void omap2_mcbsp2_mux_setup(void)
{
@ -156,7 +57,8 @@ static struct omap_mcbsp_platform_data omap2420_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP1_IRQ_RX,
.tx_irq = INT_24XX_MCBSP1_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP24XX_MCBSP2_BASE,
@ -165,7 +67,8 @@ static struct omap_mcbsp_platform_data omap2420_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP2_IRQ_RX,
.tx_irq = INT_24XX_MCBSP2_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
};
#define OMAP2420_MCBSP_PDATA_SZ ARRAY_SIZE(omap2420_mcbsp_pdata)
@ -183,7 +86,8 @@ static struct omap_mcbsp_platform_data omap2430_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP1_IRQ_RX,
.tx_irq = INT_24XX_MCBSP1_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP24XX_MCBSP2_BASE,
@ -192,7 +96,8 @@ static struct omap_mcbsp_platform_data omap2430_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP2_IRQ_RX,
.tx_irq = INT_24XX_MCBSP2_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP2430_MCBSP3_BASE,
@ -201,7 +106,8 @@ static struct omap_mcbsp_platform_data omap2430_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP3_IRQ_RX,
.tx_irq = INT_24XX_MCBSP3_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP2430_MCBSP4_BASE,
@ -210,7 +116,8 @@ static struct omap_mcbsp_platform_data omap2430_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP4_IRQ_RX,
.tx_irq = INT_24XX_MCBSP4_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP2430_MCBSP5_BASE,
@ -219,7 +126,8 @@ static struct omap_mcbsp_platform_data omap2430_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP5_IRQ_RX,
.tx_irq = INT_24XX_MCBSP5_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
};
#define OMAP2430_MCBSP_PDATA_SZ ARRAY_SIZE(omap2430_mcbsp_pdata)
@ -237,7 +145,8 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP1_IRQ_RX,
.tx_irq = INT_24XX_MCBSP1_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP34XX_MCBSP2_BASE,
@ -246,7 +155,8 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP2_IRQ_RX,
.tx_irq = INT_24XX_MCBSP2_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP34XX_MCBSP3_BASE,
@ -255,7 +165,8 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP3_IRQ_RX,
.tx_irq = INT_24XX_MCBSP3_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP34XX_MCBSP4_BASE,
@ -264,7 +175,8 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP4_IRQ_RX,
.tx_irq = INT_24XX_MCBSP4_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
{
.phys_base = OMAP34XX_MCBSP5_BASE,
@ -273,7 +185,8 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
.rx_irq = INT_24XX_MCBSP5_IRQ_RX,
.tx_irq = INT_24XX_MCBSP5_IRQ_TX,
.ops = &omap2_mcbsp_ops,
.clk_name = "mcbsp_clk",
.clk_names = clk_names,
.num_clks = 2,
},
};
#define OMAP34XX_MCBSP_PDATA_SZ ARRAY_SIZE(omap34xx_mcbsp_pdata)
@ -284,14 +197,6 @@ static struct omap_mcbsp_platform_data omap34xx_mcbsp_pdata[] = {
static int __init omap2_mcbsp_init(void)
{
int i;
for (i = 0; i < omap_mcbsp_clks_size; i++) {
/* Once we call clk_get inside init, we do not register it */
omap_mcbsp_clk_init(&omap_mcbsp_clks[i]);
clk_register(&omap_mcbsp_clks[i].clk);
}
if (cpu_is_omap2420())
omap_mcbsp_count = OMAP2420_MCBSP_PDATA_SZ;
if (cpu_is_omap2430())

View File

@ -344,7 +344,8 @@ struct omap_mcbsp_platform_data {
u8 dma_rx_sync, dma_tx_sync;
u16 rx_irq, tx_irq;
struct omap_mcbsp_ops *ops;
char const *clk_name;
char const **clk_names;
int num_clks;
};
struct omap_mcbsp {
@ -376,7 +377,8 @@ struct omap_mcbsp {
/* Protect the field .free, while checking if the mcbsp is in use */
spinlock_t lock;
struct omap_mcbsp_platform_data *pdata;
struct clk *clk;
struct clk **clks;
int num_clks;
};
extern struct omap_mcbsp **mcbsp_ptr;
extern int omap_mcbsp_count;

View File

@ -214,6 +214,7 @@ EXPORT_SYMBOL(omap_mcbsp_set_io_type);
int omap_mcbsp_request(unsigned int id)
{
struct omap_mcbsp *mcbsp;
int i;
int err;
if (!omap_mcbsp_check_valid_id(id)) {
@ -225,7 +226,8 @@ int omap_mcbsp_request(unsigned int id)
if (mcbsp->pdata && mcbsp->pdata->ops && mcbsp->pdata->ops->request)
mcbsp->pdata->ops->request(id);
clk_enable(mcbsp->clk);
for (i = 0; i < mcbsp->num_clks; i++)
clk_enable(mcbsp->clks[i]);
spin_lock(&mcbsp->lock);
if (!mcbsp->free) {
@ -276,6 +278,7 @@ EXPORT_SYMBOL(omap_mcbsp_request);
void omap_mcbsp_free(unsigned int id)
{
struct omap_mcbsp *mcbsp;
int i;
if (!omap_mcbsp_check_valid_id(id)) {
printk(KERN_ERR "%s: Invalid id (%d)\n", __func__, id + 1);
@ -286,7 +289,8 @@ void omap_mcbsp_free(unsigned int id)
if (mcbsp->pdata && mcbsp->pdata->ops && mcbsp->pdata->ops->free)
mcbsp->pdata->ops->free(id);
clk_disable(mcbsp->clk);
for (i = mcbsp->num_clks - 1; i >= 0; i--)
clk_disable(mcbsp->clks[i]);
spin_lock(&mcbsp->lock);
if (mcbsp->free) {
@ -872,6 +876,7 @@ static int __devinit omap_mcbsp_probe(struct platform_device *pdev)
struct omap_mcbsp_platform_data *pdata = pdev->dev.platform_data;
struct omap_mcbsp *mcbsp;
int id = pdev->id - 1;
int i;
int ret = 0;
if (!pdata) {
@ -916,14 +921,25 @@ static int __devinit omap_mcbsp_probe(struct platform_device *pdev)
mcbsp->dma_rx_sync = pdata->dma_rx_sync;
mcbsp->dma_tx_sync = pdata->dma_tx_sync;
if (pdata->clk_name)
mcbsp->clk = clk_get(&pdev->dev, pdata->clk_name);
if (IS_ERR(mcbsp->clk)) {
dev_err(&pdev->dev,
"Invalid clock configuration for McBSP%d.\n",
mcbsp->id);
ret = PTR_ERR(mcbsp->clk);
goto err_clk;
if (pdata->num_clks) {
mcbsp->num_clks = pdata->num_clks;
mcbsp->clks = kzalloc(mcbsp->num_clks * sizeof(struct clk *),
GFP_KERNEL);
if (!mcbsp->clks) {
ret = -ENOMEM;
goto exit;
}
for (i = 0; i < mcbsp->num_clks; i++) {
mcbsp->clks[i] = clk_get(&pdev->dev, pdata->clk_names[i]);
if (IS_ERR(mcbsp->clks[i])) {
dev_err(&pdev->dev,
"Invalid %s configuration for McBSP%d.\n",
pdata->clk_names[i], mcbsp->id);
ret = PTR_ERR(mcbsp->clks[i]);
goto err_clk;
}
}
}
mcbsp->pdata = pdata;
@ -932,6 +948,9 @@ static int __devinit omap_mcbsp_probe(struct platform_device *pdev)
return 0;
err_clk:
while (i--)
clk_put(mcbsp->clks[i]);
kfree(mcbsp->clks);
iounmap(mcbsp->io_base);
err_ioremap:
mcbsp->free = 0;
@ -942,6 +961,7 @@ exit:
static int __devexit omap_mcbsp_remove(struct platform_device *pdev)
{
struct omap_mcbsp *mcbsp = platform_get_drvdata(pdev);
int i;
platform_set_drvdata(pdev, NULL);
if (mcbsp) {
@ -950,12 +970,18 @@ static int __devexit omap_mcbsp_remove(struct platform_device *pdev)
mcbsp->pdata->ops->free)
mcbsp->pdata->ops->free(mcbsp->id);
clk_disable(mcbsp->clk);
clk_put(mcbsp->clk);
for (i = mcbsp->num_clks - 1; i >= 0; i--) {
clk_disable(mcbsp->clks[i]);
clk_put(mcbsp->clks[i]);
}
iounmap(mcbsp->io_base);
mcbsp->clk = NULL;
if (mcbsp->num_clks) {
kfree(mcbsp->clks);
mcbsp->clks = NULL;
mcbsp->num_clks = 0;
}
mcbsp->free = 0;
mcbsp->dev = NULL;
}