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can: kvaser_pciefd: the PWM generator is running at the bus frequency of the system.

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The system clock frequency for the bus connected to the PCIe controller
shall be used when calculating the frequency of the PWM, not the CAN
system clock frequency.

Signed-off-by: Christer Beskow <chbe@kvaser.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Christer Beskow 2019-08-27 17:13:26 +02:00 committed by Marc Kleine-Budde
parent 67538eb5c0
commit ec44dd5790
1 changed files with 5 additions and 1 deletions
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6
drivers/net/can/kvaser_pciefd.c
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@ -65,6 +65,7 @@ MODULE_DESCRIPTION("CAN driver for Kvaser CAN/PCIe devices");
#define KVASER_PCIEFD_SYSID_BASE 0x1f020
#define KVASER_PCIEFD_SYSID_VERSION_REG (KVASER_PCIEFD_SYSID_BASE + 0x8)
#define KVASER_PCIEFD_SYSID_CANFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0xc)
#define KVASER_PCIEFD_SYSID_BUSFREQ_REG (KVASER_PCIEFD_SYSID_BASE + 0x10)
#define KVASER_PCIEFD_SYSID_BUILD_REG (KVASER_PCIEFD_SYSID_BASE + 0x14)
/* Shared receive buffer registers */
#define KVASER_PCIEFD_SRB_BASE 0x1f200
@ -268,6 +269,7 @@ struct kvaser_pciefd {
struct kvaser_pciefd_can *can[KVASER_PCIEFD_MAX_CAN_CHANNELS];
void *dma_data[KVASER_PCIEFD_DMA_COUNT];
u8 nr_channels;
u32 bus_freq;
u32 freq;
u32 freq_to_ticks_div;
};
@ -666,7 +668,7 @@ static void kvaser_pciefd_pwm_start(struct kvaser_pciefd_can *can)
spin_lock_irqsave(&can->lock, irq);
/* Set frequency to 500 KHz*/
top = can->can.clock.freq / (2 * 500000) - 1;
top = can->kv_pcie->bus_freq / (2 * 500000) - 1;
pwm_ctrl = top & 0xff;
pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
@ -1119,6 +1121,8 @@ static int kvaser_pciefd_setup_board(struct kvaser_pciefd *pcie)
return -ENODEV;
}
pcie->bus_freq = ioread32(pcie->reg_base +
KVASER_PCIEFD_SYSID_BUSFREQ_REG);
pcie->freq = ioread32(pcie->reg_base + KVASER_PCIEFD_SYSID_CANFREQ_REG);
pcie->freq_to_ticks_div = pcie->freq / 1000000;
if (pcie->freq_to_ticks_div == 0)