Re: [PATCH v11 15/27] iommu/exynos: use convenient macro to handle gate clocks

From: Tomasz Figa
Date: Tue Mar 18 2014 - 09:08:11 EST

On 18.03.2014 12:18, Sachin Kamat wrote:
On 18 March 2014 16:33, Cho KyongHo <pullip.cho@xxxxxxxxxxx> wrote:
On Fri, 14 Mar 2014 22:27:59 +0530, Sachin Kamat wrote:
Hi KyongHo,

On 14 March 2014 19:13, Tomasz Figa <t.figa@xxxxxxxxxxx> wrote:
Hi KyongHo,

On 14.03.2014 06:09, Cho KyongHo wrote:

exynos-iommu driver must care about master H/W's gate clock as well as
System MMU's gate clock. To enhance readability of the source code,
macros to gate/ungate those clocks are defined.

Signed-off-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
drivers/iommu/exynos-iommu.c | 34 ++++++++++++++++++++++------------
1 file changed, 22 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 71e77f1..cef62d0 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -101,6 +101,16 @@
#define REG_PB1_SADDR 0x054
#define REG_PB1_EADDR 0x058

+#define __clk_gate_ctrl(data, clk, en) do { \
+ if (data->clk) \
+ clk_##en##able(data->clk); \
+ } while (0)
+#define __sysmmu_clk_enable(data) __clk_gate_ctrl(data, clk, en)
+#define __sysmmu_clk_disable(data) __clk_gate_ctrl(data, clk, dis)
+#define __master_clk_enable(data) __clk_gate_ctrl(data, clk_master,
+#define __master_clk_disable(data) __clk_gate_ctrl(data, clk_master,

I'd say that such macros only obfuscate code, without any gains, as you can
see in diffstat - this patch adds more lines than it removes.

Please drop this change.

I agree with Tomasz here.

Are you concerning about using macros or more insertions than deletions?

It is just making the code more difficult to read and understand.

Especially when hiding accesses to struct fields inside and doing fancy stuff like concatenations.

Best regards,
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