diff options
| author | Simon Horman <horms+renesas@verge.net.au> | 2015-11-20 19:29:39 (GMT) |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-11-20 19:52:37 (GMT) |
| commit | b3d39a8805c5109dde960204806cf540e3be12fa (patch) | |
| tree | b52caf6ca83bbec15847e69cc97c3736cd822872 | |
| parent | 1777ddb84a543444d44594d437b0f3d3f8734f32 (diff) | |
| download | linux-b3d39a8805c5109dde960204806cf540e3be12fa.tar.xz | |
ravb: use clock rate as basis for GTI.TIV
The GTI.TIV may be set to 2GHz^2 / rate, where rate is
that of the clock of the device. Rather than assuming a
rate of 130MHz use the actual rate of the clock.
The motivation for this is to use the correct rate on
the r8a7795/Salvator-X which is advertised as 133MHz but
may differ depending on the extal present on the Salvator-X.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/ethernet/renesas/ravb.h | 3 | ||||
| -rw-r--r-- | drivers/net/ethernet/renesas/ravb_main.c | 38 |
2 files changed, 40 insertions, 1 deletions
diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index 0623fff9..f9dee74 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -576,6 +576,9 @@ enum GTI_BIT { GTI_TIV = 0x0FFFFFFF, }; +#define GTI_TIV_MAX GTI_TIV +#define GTI_TIV_MIN 0x20 + /* GIC */ enum GIC_BIT { GIC_PTCE = 0x00000001, /* Undocumented? */ diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index ee8d1ec..990dc55 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -32,6 +32,8 @@ #include <linux/slab.h> #include <linux/spinlock.h> +#include <asm/div64.h> + #include "ravb.h" #define RAVB_DEF_MSG_ENABLE \ @@ -1659,6 +1661,38 @@ static const struct of_device_id ravb_match_table[] = { }; MODULE_DEVICE_TABLE(of, ravb_match_table); +static int ravb_set_gti(struct net_device *ndev) +{ + + struct device *dev = ndev->dev.parent; + struct device_node *np = dev->of_node; + unsigned long rate; + struct clk *clk; + uint64_t inc; + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + dev_err(dev, "could not get clock\n"); + return PTR_ERR(clk); + } + + rate = clk_get_rate(clk); + clk_put(clk); + + inc = 1000000000ULL << 20; + do_div(inc, rate); + + if (inc < GTI_TIV_MIN || inc > GTI_TIV_MAX) { + dev_err(dev, "gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n", + inc, GTI_TIV_MIN, GTI_TIV_MAX); + return -EINVAL; + } + + ravb_write(ndev, inc, GTI); + + return 0; +} + static int ravb_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; @@ -1755,7 +1789,9 @@ static int ravb_probe(struct platform_device *pdev) CCC); /* Set GTI value */ - ravb_write(ndev, ((1000 << 20) / 130) & GTI_TIV, GTI); + error = ravb_set_gti(ndev); + if (error) + goto out_release; /* Request GTI loading */ ravb_write(ndev, ravb_read(ndev, GCCR) | GCCR_LTI, GCCR); |