[linux-yocto] [PATCH 14/35] arch/arm/mach-axxia: Check Status and Add Locks to NCR Accesses
Bruce Ashfield
bruce.ashfield at windriver.com
Sun Nov 16 20:43:55 PST 2014
On 2014-11-13, 12:19 PM, Daniel Dragomir wrote:
> From: John Jacques <john.jacques at lsi.com>
>
> Signed-off-by: John Jacques <john.jacques at lsi.com>
> ---
> arch/arm/mach-axxia/ncr.c | 73 +++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 64 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm/mach-axxia/ncr.c b/arch/arm/mach-axxia/ncr.c
> index 51fcf66..995e8a0 100644
> --- a/arch/arm/mach-axxia/ncr.c
> +++ b/arch/arm/mach-axxia/ncr.c
> @@ -40,6 +40,9 @@ static void __iomem *apb2ser0_address;
>
> #define WFC_TIMEOUT (400000)
>
> +static DEFINE_RAW_SPINLOCK(ncr_spin_lock);
> +static unsigned long flags;
> +
> #define LOCK_DOMAIN 0
>
> typedef union {
> @@ -170,15 +173,48 @@ ncr_lock(int domain)
> unsigned long offset;
> unsigned long value;
> int loops = 10000;
> + command_data_register_0_t cdr0;
>
> + raw_spin_lock_irqsave(&ncr_spin_lock, flags);
When using raw_* locks, we should have an explanation of why the standard
spinlock variants won't work.
Bruce
> offset = (0xff80 + (domain * 4));
>
> do {
> value = ncr_register_read((unsigned *)(nca_address + offset));
> } while ((0 != value) && (0 < --loops));
>
> - if (0 == loops)
> + if (0 == loops) {
> + raw_spin_unlock_irqrestore(&ncr_spin_lock, flags);
> + printk(KERN_ERR "ncr_lock() Timeout!\n");
> + BUG();
> +
> + return -1;
> + }
> +
> + /*
> + Make sure any previous commands completed, and check for errors.
> + */
> +
> + loops = 10000;
> +
> + do {
> + --loops;
> + cdr0.raw =
> + ncr_register_read((unsigned *)(nca_address + 0xf0));
> + } while ((0x1 == cdr0.bits.status) &&
> + (0 < loops));
> +
> + if (0 == loops) {
> + raw_spin_unlock_irqrestore(&ncr_spin_lock, flags);
> + printk(KERN_ERR
> + "ncr_lock() Previous command didn't complete!\n");
> + BUG();
> +
> return -1;
> + }
> +
> + if (0x2 == cdr0.bits.status) {
> + printk(KERN_ERR "Previous ncr access failed!\n");
> + }
>
> return 0;
> }
> @@ -195,6 +231,7 @@ ncr_unlock(int domain)
>
> offset = (0xff80 + (domain * 4));
> ncr_register_write(0, (unsigned *)(nca_address + offset));
> + raw_spin_unlock_irqrestore(&ncr_spin_lock, flags);
>
> return;
> }
> @@ -264,12 +301,24 @@ ncr_read(unsigned long region, unsigned long address, int number,
>
> do {
> --wfc_timeout;
> - } while ((0x80000000UL ==
> - ncr_register_read((unsigned *)(nca_address + 0xf0))) &&
> - 0 < wfc_timeout);
> + cdr0.raw =
> + ncr_register_read((unsigned *)
> + (nca_address + 0xf0));
> + } while (1 == cdr0.bits.start_done && 0 < wfc_timeout);
>
> if (0 == wfc_timeout) {
> ncr_unlock(LOCK_DOMAIN);
> + printk(KERN_ERR "ncr_read() Timeout!\n");
> + BUG();
> +
> + return -1;
> + }
> +
> + if (0x3 != cdr0.bits.status) {
> + ncr_unlock(LOCK_DOMAIN);
> + printk(KERN_ERR "ncr_write() failed: 0x%x\n",
> + cdr0.bits.status);
> +
> return -1;
> }
>
> @@ -459,12 +508,16 @@ ncr_write(unsigned long region, unsigned long address, int number,
>
> do {
> --wfc_timeout;
> - } while ((0x80000000UL ==
> - ncr_register_read((unsigned *)(nca_address + 0xf0))) &&
> - 0 < wfc_timeout);
> + cdr0.raw =
> + ncr_register_read((unsigned *)
> + (nca_address + 0xf0));
> + } while (1 == cdr0.bits.start_done && 0 < wfc_timeout);
>
> if (0 == wfc_timeout) {
> ncr_unlock(LOCK_DOMAIN);
> + printk(KERN_ERR "ncr_write() Timeout!\n");
> + BUG();
> +
> return -1;
> }
>
> @@ -472,13 +525,15 @@ ncr_write(unsigned long region, unsigned long address, int number,
> Check status.
> */
>
> - if (0x3 != ((ncr_register_read((unsigned *) (nca_address + 0xf0)) &
> - 0x00c00000) >> 22)) {
> + if ((0x3 != cdr0.bits.status) && (0x00c00000) >> 22) {
> unsigned long status;
>
> status = ncr_register_read((unsigned *)(nca_address +
> 0xe4));
> ncr_unlock(LOCK_DOMAIN);
> + printk(KERN_ERR
> + "ncr_write() Error: 0x%x 0x%lx\n",
> + cdr0.bits.status, status);
>
> return status;
> }
>
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