[PATCH V6 06/11] misc: xilinx_sdfec: Add ability to configure LDPC

From: Dragan Cvetic
Date: Mon Jun 10 2019 - 09:50:18 EST


Add the capability to configure LDPC mode via the ioctl
XSDFEC_ADD_LDPC_CODE_PARAMS.

Tested-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx>
Signed-off-by: Derek Kiernan <derek.kiernan@xxxxxxxxxx>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx>
---
drivers/misc/xilinx_sdfec.c | 324 +++++++++++++++++++++++++++++++++++++++
include/uapi/misc/xilinx_sdfec.h | 98 ++++++++++++
2 files changed, 422 insertions(+)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 37107dd..b2b16771 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -20,6 +20,7 @@
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/compat.h>
+#include <linux/highmem.h>

#include <uapi/misc/xilinx_sdfec.h>

@@ -113,6 +114,57 @@ static struct mutex dev_idr_lock;
#define XSDFEC_TURBO_SCALE_BIT_POS (8)
#define XSDFEC_TURBO_SCALE_MAX (15)

+/* REG0 Register */
+#define XSDFEC_LDPC_CODE_REG0_ADDR_BASE (0x2000)
+#define XSDFEC_LDPC_CODE_REG0_ADDR_HIGH (0x27F0)
+#define XSDFEC_REG0_N_MIN (4)
+#define XSDFEC_REG0_N_MAX (32768)
+#define XSDFEC_REG0_N_MUL_P (256)
+#define XSDFEC_REG0_N_LSB (0)
+#define XSDFEC_REG0_K_MIN (2)
+#define XSDFEC_REG0_K_MAX (32766)
+#define XSDFEC_REG0_K_MUL_P (256)
+#define XSDFEC_REG0_K_LSB (16)
+
+/* REG1 Register */
+#define XSDFEC_LDPC_CODE_REG1_ADDR_BASE (0x2004)
+#define XSDFEC_LDPC_CODE_REG1_ADDR_HIGH (0x27f4)
+#define XSDFEC_REG1_PSIZE_MIN (2)
+#define XSDFEC_REG1_PSIZE_MAX (512)
+#define XSDFEC_REG1_NO_PACKING_MASK (0x400)
+#define XSDFEC_REG1_NO_PACKING_LSB (10)
+#define XSDFEC_REG1_NM_MASK (0xFF800)
+#define XSDFEC_REG1_NM_LSB (11)
+#define XSDFEC_REG1_BYPASS_MASK (0x100000)
+
+/* REG2 Register */
+#define XSDFEC_LDPC_CODE_REG2_ADDR_BASE (0x2008)
+#define XSDFEC_LDPC_CODE_REG2_ADDR_HIGH (0x27f8)
+#define XSDFEC_REG2_NLAYERS_MIN (1)
+#define XSDFEC_REG2_NLAYERS_MAX (256)
+#define XSDFEC_REG2_NNMQC_MASK (0xFFE00)
+#define XSDFEC_REG2_NMQC_LSB (9)
+#define XSDFEC_REG2_NORM_TYPE_MASK (0x100000)
+#define XSDFEC_REG2_NORM_TYPE_LSB (20)
+#define XSDFEC_REG2_SPECIAL_QC_MASK (0x200000)
+#define XSDFEC_REG2_SPEICAL_QC_LSB (21)
+#define XSDFEC_REG2_NO_FINAL_PARITY_MASK (0x400000)
+#define XSDFEC_REG2_NO_FINAL_PARITY_LSB (22)
+#define XSDFEC_REG2_MAX_SCHEDULE_MASK (0x1800000)
+#define XSDFEC_REG2_MAX_SCHEDULE_LSB (23)
+
+/* REG3 Register */
+#define XSDFEC_LDPC_CODE_REG3_ADDR_BASE (0x200C)
+#define XSDFEC_LDPC_CODE_REG3_ADDR_HIGH (0x27FC)
+#define XSDFEC_REG3_LA_OFF_LSB (8)
+#define XSDFEC_REG3_QC_OFF_LSB (16)
+
+#define XSDFEC_LDPC_REG_JUMP (0x10)
+#define XSDFEC_REG_WIDTH_JUMP (4)
+
+/* The maximum number of pinned pages */
+#define MAX_NUM_PAGES ((XSDFEC_QC_TABLE_DEPTH / PAGE_SIZE) + 1)
+
/**
* struct xsdfec_clks - For managing SD-FEC clocks
* @core_clk: Main processing clock for core
@@ -270,6 +322,275 @@ static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
return err;
}

+static int xsdfec_reg0_write(struct xsdfec_dev *xsdfec, u32 n, u32 k, u32 psize,
+ u32 offset)
+{
+ u32 wdata;
+
+ if (n < XSDFEC_REG0_N_MIN || n > XSDFEC_REG0_N_MAX ||
+ (n > XSDFEC_REG0_N_MUL_P * psize) || n <= k || ((n % psize) != 0)) {
+ dev_dbg(xsdfec->dev, "N value is not in range");
+ return -EINVAL;
+ }
+ n <<= XSDFEC_REG0_N_LSB;
+
+ if (k < XSDFEC_REG0_K_MIN || k > XSDFEC_REG0_K_MAX ||
+ (k > XSDFEC_REG0_K_MUL_P * psize) || ((k % psize) != 0)) {
+ dev_dbg(xsdfec->dev, "K value is not in range");
+ return -EINVAL;
+ }
+ k = k << XSDFEC_REG0_K_LSB;
+ wdata = k | n;
+
+ if (XSDFEC_LDPC_CODE_REG0_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+ XSDFEC_LDPC_CODE_REG0_ADDR_HIGH) {
+ dev_dbg(xsdfec->dev, "Writing outside of LDPC reg0 space 0x%x",
+ XSDFEC_LDPC_CODE_REG0_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP));
+ return -EINVAL;
+ }
+ xsdfec_regwrite(xsdfec,
+ XSDFEC_LDPC_CODE_REG0_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP),
+ wdata);
+ return 0;
+}
+
+static int xsdfec_reg1_write(struct xsdfec_dev *xsdfec, u32 psize,
+ u32 no_packing, u32 nm, u32 offset)
+{
+ u32 wdata;
+
+ if (psize < XSDFEC_REG1_PSIZE_MIN || psize > XSDFEC_REG1_PSIZE_MAX) {
+ dev_dbg(xsdfec->dev, "Psize is not in range");
+ return -EINVAL;
+ }
+
+ if (no_packing != 0 && no_packing != 1)
+ dev_dbg(xsdfec->dev, "No-packing bit register invalid");
+ no_packing = ((no_packing << XSDFEC_REG1_NO_PACKING_LSB) &
+ XSDFEC_REG1_NO_PACKING_MASK);
+
+ if (nm & ~(XSDFEC_REG1_NM_MASK >> XSDFEC_REG1_NM_LSB))
+ dev_dbg(xsdfec->dev, "NM is beyond 10 bits");
+ nm = (nm << XSDFEC_REG1_NM_LSB) & XSDFEC_REG1_NM_MASK;
+
+ wdata = nm | no_packing | psize;
+ if (XSDFEC_LDPC_CODE_REG1_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+ XSDFEC_LDPC_CODE_REG1_ADDR_HIGH) {
+ dev_dbg(xsdfec->dev, "Writing outside of LDPC reg1 space 0x%x",
+ XSDFEC_LDPC_CODE_REG1_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP));
+ return -EINVAL;
+ }
+ xsdfec_regwrite(xsdfec,
+ XSDFEC_LDPC_CODE_REG1_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP),
+ wdata);
+ return 0;
+}
+
+static int xsdfec_reg2_write(struct xsdfec_dev *xsdfec, u32 nlayers, u32 nmqc,
+ u32 norm_type, u32 special_qc, u32 no_final_parity,
+ u32 max_schedule, u32 offset)
+{
+ u32 wdata;
+
+ if (nlayers < XSDFEC_REG2_NLAYERS_MIN ||
+ nlayers > XSDFEC_REG2_NLAYERS_MAX) {
+ dev_dbg(xsdfec->dev, "Nlayers is not in range");
+ return -EINVAL;
+ }
+
+ if (nmqc & ~(XSDFEC_REG2_NNMQC_MASK >> XSDFEC_REG2_NMQC_LSB))
+ dev_dbg(xsdfec->dev, "NMQC exceeds 11 bits");
+ nmqc = (nmqc << XSDFEC_REG2_NMQC_LSB) & XSDFEC_REG2_NNMQC_MASK;
+
+ if (norm_type > 1)
+ dev_dbg(xsdfec->dev, "Norm type is invalid");
+ norm_type = ((norm_type << XSDFEC_REG2_NORM_TYPE_LSB) &
+ XSDFEC_REG2_NORM_TYPE_MASK);
+ if (special_qc > 1)
+ dev_dbg(xsdfec->dev, "Special QC in invalid");
+ special_qc = ((special_qc << XSDFEC_REG2_SPEICAL_QC_LSB) &
+ XSDFEC_REG2_SPECIAL_QC_MASK);
+
+ if (no_final_parity > 1)
+ dev_dbg(xsdfec->dev, "No final parity check invalid");
+ no_final_parity =
+ ((no_final_parity << XSDFEC_REG2_NO_FINAL_PARITY_LSB) &
+ XSDFEC_REG2_NO_FINAL_PARITY_MASK);
+ if (max_schedule &
+ ~(XSDFEC_REG2_MAX_SCHEDULE_MASK >> XSDFEC_REG2_MAX_SCHEDULE_LSB))
+ dev_dbg(xsdfec->dev, "Max Schdule exceeds 2 bits");
+ max_schedule = ((max_schedule << XSDFEC_REG2_MAX_SCHEDULE_LSB) &
+ XSDFEC_REG2_MAX_SCHEDULE_MASK);
+
+ wdata = (max_schedule | no_final_parity | special_qc | norm_type |
+ nmqc | nlayers);
+
+ if (XSDFEC_LDPC_CODE_REG2_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+ XSDFEC_LDPC_CODE_REG2_ADDR_HIGH) {
+ dev_dbg(xsdfec->dev, "Writing outside of LDPC reg2 space 0x%x",
+ XSDFEC_LDPC_CODE_REG2_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP));
+ return -EINVAL;
+ }
+ xsdfec_regwrite(xsdfec,
+ XSDFEC_LDPC_CODE_REG2_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP),
+ wdata);
+ return 0;
+}
+
+static int xsdfec_reg3_write(struct xsdfec_dev *xsdfec, u8 sc_off, u8 la_off,
+ u16 qc_off, u32 offset)
+{
+ u32 wdata;
+
+ wdata = ((qc_off << XSDFEC_REG3_QC_OFF_LSB) |
+ (la_off << XSDFEC_REG3_LA_OFF_LSB) | sc_off);
+ if (XSDFEC_LDPC_CODE_REG3_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+ XSDFEC_LDPC_CODE_REG3_ADDR_HIGH) {
+ dev_dbg(xsdfec->dev, "Writing outside of LDPC reg3 space 0x%x",
+ XSDFEC_LDPC_CODE_REG3_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP));
+ return -EINVAL;
+ }
+ xsdfec_regwrite(xsdfec,
+ XSDFEC_LDPC_CODE_REG3_ADDR_BASE +
+ (offset * XSDFEC_LDPC_REG_JUMP),
+ wdata);
+ return 0;
+}
+
+static int xsdfec_table_write(struct xsdfec_dev *xsdfec, u32 offset,
+ u32 *src_ptr, u32 len, const u32 base_addr,
+ const u32 depth)
+{
+ u32 reg = 0;
+ u32 res;
+ u32 n, i;
+ u32 *addr = NULL;
+ struct page *page[MAX_NUM_PAGES];
+
+ /*
+ * Writes that go beyond the length of
+ * Shared Scale(SC) table should fail
+ */
+ if ((XSDFEC_REG_WIDTH_JUMP * (offset + len)) > depth) {
+ dev_dbg(xsdfec->dev, "Write exceeds SC table length");
+ return -EINVAL;
+ }
+
+ n = (len * XSDFEC_REG_WIDTH_JUMP) / PAGE_SIZE;
+ if ((len * XSDFEC_REG_WIDTH_JUMP) % PAGE_SIZE)
+ n += 1;
+
+ res = get_user_pages_fast((unsigned long)src_ptr, n, 0, page);
+ if (res < n) {
+ for (i = 0; i < res; i++)
+ put_page(page[i]);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < n; i++) {
+ addr = kmap(page[i]);
+ do {
+ xsdfec_regwrite(xsdfec,
+ base_addr + ((offset + reg) *
+ XSDFEC_REG_WIDTH_JUMP),
+ addr[reg]);
+ reg++;
+ } while ((reg < len) &&
+ ((reg * XSDFEC_REG_WIDTH_JUMP) % PAGE_SIZE));
+ put_page(page[i]);
+ }
+ return reg;
+}
+
+static int xsdfec_add_ldpc(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+ struct xsdfec_ldpc_params *ldpc;
+ int ret, n;
+
+ ldpc = kzalloc(sizeof(*ldpc), GFP_KERNEL);
+ if (!ldpc)
+ return -ENOMEM;
+
+ ret = copy_from_user(ldpc, arg, sizeof(*ldpc));
+ if (ret)
+ goto err_out;
+
+ if (xsdfec->config.code == XSDFEC_TURBO_CODE) {
+ ret = -EIO;
+ goto err_out;
+ }
+
+ /* Verify Device has not started */
+ if (xsdfec->state == XSDFEC_STARTED) {
+ ret = -EIO;
+ goto err_out;
+ }
+
+ if (xsdfec->config.code_wr_protect) {
+ ret = -EIO;
+ goto err_out;
+ }
+
+ /* Write Reg 0 */
+ ret = xsdfec_reg0_write(xsdfec, ldpc->n, ldpc->k, ldpc->psize,
+ ldpc->code_id);
+ if (ret)
+ goto err_out;
+
+ /* Write Reg 1 */
+ ret = xsdfec_reg1_write(xsdfec, ldpc->psize, ldpc->no_packing, ldpc->nm,
+ ldpc->code_id);
+ if (ret)
+ goto err_out;
+
+ /* Write Reg 2 */
+ ret = xsdfec_reg2_write(xsdfec, ldpc->nlayers, ldpc->nmqc,
+ ldpc->norm_type, ldpc->special_qc,
+ ldpc->no_final_parity, ldpc->max_schedule,
+ ldpc->code_id);
+ if (ret)
+ goto err_out;
+
+ /* Write Reg 3 */
+ ret = xsdfec_reg3_write(xsdfec, ldpc->sc_off, ldpc->la_off,
+ ldpc->qc_off, ldpc->code_id);
+ if (ret)
+ goto err_out;
+
+ /* Write Shared Codes */
+ n = ldpc->nlayers / 4;
+ if (ldpc->nlayers % 4)
+ n++;
+
+ ret = xsdfec_table_write(xsdfec, ldpc->sc_off, ldpc->sc_table, n,
+ XSDFEC_LDPC_SC_TABLE_ADDR_BASE,
+ XSDFEC_SC_TABLE_DEPTH);
+ if (ret < 0)
+ goto err_out;
+
+ ret = xsdfec_table_write(xsdfec, 4 * ldpc->la_off, ldpc->la_table,
+ ldpc->nlayers, XSDFEC_LDPC_LA_TABLE_ADDR_BASE,
+ XSDFEC_LA_TABLE_DEPTH);
+ if (ret < 0)
+ goto err_out;
+
+ ret = xsdfec_table_write(xsdfec, 4 * ldpc->qc_off, ldpc->qc_table,
+ ldpc->nqc, XSDFEC_LDPC_QC_TABLE_ADDR_BASE,
+ XSDFEC_QC_TABLE_DEPTH);
+ if (ret > 0)
+ ret = 0;
+err_out:
+ kfree(ldpc);
+ return ret;
+}
+
static u32
xsdfec_translate_axis_width_cfg_val(enum xsdfec_axis_width axis_width_cfg)
{
@@ -366,6 +687,9 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
case XSDFEC_GET_TURBO:
rval = xsdfec_get_turbo(xsdfec, arg);
break;
+ case XSDFEC_ADD_LDPC_CODE_PARAMS:
+ rval = xsdfec_add_ldpc(xsdfec, arg);
+ break;
default:
/* Should not get here */
break;
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index 8be14cf..7443ed8 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -13,6 +13,22 @@

#include <linux/types.h>

+/* Shared LDPC Tables */
+#define XSDFEC_LDPC_SC_TABLE_ADDR_BASE (0x10000)
+#define XSDFEC_LDPC_SC_TABLE_ADDR_HIGH (0x10400)
+#define XSDFEC_LDPC_LA_TABLE_ADDR_BASE (0x18000)
+#define XSDFEC_LDPC_LA_TABLE_ADDR_HIGH (0x19000)
+#define XSDFEC_LDPC_QC_TABLE_ADDR_BASE (0x20000)
+#define XSDFEC_LDPC_QC_TABLE_ADDR_HIGH (0x28000)
+
+/* LDPC tables depth */
+#define XSDFEC_SC_TABLE_DEPTH \
+ (XSDFEC_LDPC_SC_TABLE_ADDR_HIGH - XSDFEC_LDPC_SC_TABLE_ADDR_BASE)
+#define XSDFEC_LA_TABLE_DEPTH \
+ (XSDFEC_LDPC_LA_TABLE_ADDR_HIGH - XSDFEC_LDPC_LA_TABLE_ADDR_BASE)
+#define XSDFEC_QC_TABLE_DEPTH \
+ (XSDFEC_LDPC_QC_TABLE_ADDR_HIGH - XSDFEC_LDPC_QC_TABLE_ADDR_BASE)
+
/**
* enum xsdfec_code - Code Type.
* @XSDFEC_TURBO_CODE: Driver is configured for Turbo mode.
@@ -127,6 +143,53 @@ struct xsdfec_turbo {
};

/**
+ * struct xsdfec_ldpc_params - User data for LDPC codes.
+ * @n: Number of code word bits
+ * @k: Number of information bits
+ * @psize: Size of sub-matrix
+ * @nlayers: Number of layers in code
+ * @nqc: Quasi Cyclic Number
+ * @nmqc: Number of M-sized QC operations in parity check matrix
+ * @nm: Number of M-size vectors in N
+ * @norm_type: Normalization required or not
+ * @no_packing: Determines if multiple QC ops should be performed
+ * @special_qc: Sub-Matrix property for Circulant weight > 0
+ * @no_final_parity: Decide if final parity check needs to be performed
+ * @max_schedule: Experimental code word scheduling limit
+ * @sc_off: SC offset
+ * @la_off: LA offset
+ * @qc_off: QC offset
+ * @sc_table: Pointer to SC Table which must be page aligned
+ * @la_table: Pointer to LA Table which must be page aligned
+ * @qc_table: Pointer to QC Table which must be page aligned
+ * @code_id: LDPC Code
+ *
+ * This structure describes the LDPC code that is passed to the driver by the
+ * application.
+ */
+struct xsdfec_ldpc_params {
+ __u32 n;
+ __u32 k;
+ __u32 psize;
+ __u32 nlayers;
+ __u32 nqc;
+ __u32 nmqc;
+ __u32 nm;
+ __u32 norm_type;
+ __u32 no_packing;
+ __u32 special_qc;
+ __u32 no_final_parity;
+ __u32 max_schedule;
+ __u32 sc_off;
+ __u32 la_off;
+ __u32 qc_off;
+ __u32 *sc_table;
+ __u32 *la_table;
+ __u32 *qc_table;
+ __u16 code_id;
+};
+
+/**
* struct xsdfec_status - Status of SD-FEC core.
* @state: State of the SD-FEC core
* @activity: Describes if the SD-FEC instance is Active
@@ -170,6 +233,20 @@ struct xsdfec_config {
struct xsdfec_irq irq;
};

+/**
+ * struct xsdfec_ldpc_param_table_sizes - Used to store sizes of SD-FEC table
+ * entries for an individual LPDC code
+ * parameter.
+ * @sc_size: Size of SC table used
+ * @la_size: Size of LA table used
+ * @qc_size: Size of QC table used
+ */
+struct xsdfec_ldpc_param_table_sizes {
+ __u32 sc_size;
+ __u32 la_size;
+ __u32 qc_size;
+};
+
/*
* XSDFEC IOCTL List
*/
@@ -190,6 +267,27 @@ struct xsdfec_config {
*/
#define XSDFEC_SET_TURBO _IOW(XSDFEC_MAGIC, 4, struct xsdfec_turbo)
/**
+ * DOC: XSDFEC_ADD_LDPC_CODE_PARAMS
+ * @Parameters
+ *
+ * @struct xsdfec_ldpc_params *
+ * Pointer to the &struct xsdfec_ldpc_params that contains the LDPC code
+ * parameters to be added to the SD-FEC Block
+ *
+ * @Description
+ * ioctl to add an LDPC code to the SD-FEC LDPC codes
+ *
+ * This can only be used when:
+ *
+ * - Driver is in the XSDFEC_STOPPED state
+ *
+ * - SD-FEC core is configured as LPDC
+ *
+ * - SD-FEC Code Write Protection is disabled
+ */
+#define XSDFEC_ADD_LDPC_CODE_PARAMS \
+ _IOW(XSDFEC_MAGIC, 5, struct xsdfec_ldpc_params)
+/**
* DOC: XSDFEC_GET_TURBO
* @Parameters
*
--
2.7.4