Re: [PATCH v6 2/2] spi: cadence-quadpsi: Add support for the Cadence QSPI controller

From: Ramuthevar, Vadivel MuruganX
Date: Mon Jan 06 2020 - 06:19:33 EST


Hi,

Thank you for the review comments.

On 6/1/2020 6:40 PM, Vignesh Raghavendra wrote:
Hi,

On 30/12/19 1:11 pm, Ramuthevar,Vadivel MuruganX wrote:
[...]
+static u32 cqspi_cmd2addr(const unsigned char *addr_buf, u32 addr_width)
+{
+ unsigned int addr = 0;
+ int i;
+
+ /* Invalid address return zero. */
+ if (addr_width > 4)
+ return 0;
+
+ for (i = 0; i < addr_width; i++) {
+ addr = addr << 8;
+ addr |= addr_buf[i];
+ }
+
+ return addr;
+}
+
[...]
+static int cqspi_apb_read_setup(struct struct_cqspi *cqspi,
+ const struct spi_mem_op *op,
+ const u8 *addrbuf)
+{
+ void __iomem *reg_base = cqspi->iobase;
+ size_t addrlen = op->addr.nbytes;
+ size_t dummy_bytes = op->dummy.nbytes;
+ unsigned int addr_value, dummy_clk, reg;
+
+ if (addrlen) {
+ addr_value = cqspi_cmd2addr(&addrbuf[0], addrlen);
+ writel(addr_value, reg_base + CQSPI_REG_INDIRECTRDSTARTADDR);
+ }
+
Why do you need to swap the address bytes to SPI bus order?
Yes , you are right to align with spi bus order swap is done .
You are
writing to a controller register that accepts 24 bit or 32 bit address.
32bit address.
+ reg = op->cmd.opcode << CQSPI_REG_RD_INSTR_OPCODE_LSB;
+ reg |= (op->data.buswidth & CQSPI_REG_RD_INSTR_TYPE_DATA_MASK) <<
+ CQSPI_REG_RD_INSTR_TYPE_DATA_LSB;
+
This is wrong... op->data.buswidth's range is 1 to 8 whereas
CQSPI_REG_RD_INSTR_TYPE range is 0 to 3. I wonder whether you tested
dual/quad mode with this driver?
Yes I have tested with Quad mode since Cadence-IP supports dual/quad on my platform, used to validate
before sending the patch that's standard procedure here.
please let me know if you have any further queries.

---
Best Regards
Vadivel
I am still unable to get this series to work on my platform. Will
continue to debug...